Trigonometry

67 questions

1.42: Past-paper question 3

4PM1/1/June/2025 — Question 3 · 6 marks

1.42 diagram 1
Figure 1 shows circle C1\displaystyle C_1 with radius 7 cm and circle C2\displaystyle C_2 with centre O\displaystyle O and radius 7 cm
The circles C1\displaystyle C_1 and C2\displaystyle C_2 intersect at the point A\displaystyle A and at the point B\displaystyle B
The size of angle AOB\displaystyle AOB is θ\displaystyle \theta radians
The perimeter of the region R\displaystyle R shown shaded in Figure 1 is 28π9\displaystyle \frac{28\pi}{9} cm
(a) Find the exact value of θ\displaystyle \theta
(2)
(b) Find the area, in cm2\displaystyle \mathrm{cm}^2 to 3 significant figures, of the region R\displaystyle R
(4)

1.43: Past-paper question 8

4PM1/1/June/2025 — Question 8 · 13 marks

1.43 diagram 1
Figure 3 shows a right pyramid with vertex V\displaystyle V and square base, ABCD\displaystyle ABCD, of side 12 cm
The size of the angle between the plane VAB\displaystyle VAB and the base ABCD\displaystyle ABCD is 30\displaystyle 30^\circ
(a) Show that the height of the pyramid is 23\displaystyle 2\sqrt{3} cm
(2)
(b) Find, in cm, the exact length of VA\displaystyle VA
(3)
(c) Find, in cm2\displaystyle \mathrm{cm}^2, the exact area of triangle VAD\displaystyle VAD
(3)
(d) Find, in cm, the exact length of the perpendicular from D\displaystyle D to VA\displaystyle VA
(2)
(e) Find, in degrees to one decimal place, the size of the obtuse angle between the plane VAB\displaystyle VAB and the plane VAD\displaystyle VAD
(3)

1.51: Past-paper question 3

4PM1/1/November/2025 — Question 3 · 6 marks

1.51 diagram 1
Figure 1 shows triangle ABC\displaystyle ABC where
AB=12cmBC=15cmAC=xcmBAC=60AB = 12 \mathrm{cm} \quad BC = 15 \mathrm{cm} \quad AC = x \mathrm{cm} \quad \angle BAC = 60^\circ
(a) Show that x\displaystyle x satisfies the equation
x212x81=0x^2 - 12x - 81 = 0
(3)
(b) Hence find the exact area, in cm2\displaystyle \mathrm{cm}^2, of triangle ABC\displaystyle ABC
Give your answer in the form 9(pq+r)\displaystyle 9(p\sqrt{q} + \sqrt{r}) where p,q\displaystyle p, q and r\displaystyle r are integers.
(3)

1.52: Past-paper question 11

4PM1/1/November/2025 — Question 11 · 10 marks

(a) Using a formula on page 2, show that
1cos2A1+cos2A=tan2A\frac{1 - \mathrm{cos} 2A}{1 + \mathrm{cos} 2A} = \mathrm{tan}^2 A
(3)
(b) Hence, or otherwise, solve in degrees to one decimal place
33cos4x1+cos4x+5sin2xcos2x=2for90<x<90\frac{3 - 3 \mathrm{cos} 4x}{1 + \mathrm{cos} 4x} + \frac{5 \mathrm{sin} 2x}{\mathrm{cos} 2x} = 2 \quad \mathrm{for} -90^\circ < x < 90^\circ
(7)

1.44: Past-paper question 4

4PM1/1R/June/2025 — Question 4 · 7 marks

Triangle ABC\displaystyle ABC is such that
AB=4.3cmAB = 4.3 \mathrm{cm}
BC=5.9cmBC = 5.9 \mathrm{cm}
angleBCA=29\mathrm{angle} BCA = 29^\circ
(a) Find in degrees, to one decimal place, the two possible values for angle CAB\displaystyle CAB
(4)
(b) Hence, find in cm, to 3 significant figures, the shortest possible length of AC\displaystyle AC
(3)

1.45: Past-paper question 10

4PM1/1R/June/2025 — Question 10 · 15 marks

1.45 diagram 1
(a) Using a formula from page 2, show that
(i)sin2A=1cos2A2(i) \mathrm{sin}^2 A = \frac{1 - \mathrm{cos} 2A}{2}
(ii)cos2A=cos2A+12(ii) \mathrm{cos}^2 A = \frac{\mathrm{cos} 2A + 1}{2}
(5)
Figure 2 shows part of the curve C\displaystyle C with equation y=sinx\displaystyle y = \mathrm{sin} x and part of the curve D\displaystyle D with equation y=cos2x\displaystyle y = \mathrm{cos} 2x
Curve C\displaystyle C and curve D\displaystyle D intersect at the point A\displaystyle A
(b) Use algebra to find the exact coordinates of A\displaystyle A
(5)
The shaded region R\displaystyle R is rotated through 360\displaystyle 360^\circ about the x\displaystyle x-axis.
(c) Use algebraic integration to find the exact volume of the solid generated.
Give your answer in the form aabπ\displaystyle \frac{a\sqrt{a}}{b}\pi
where a\displaystyle a is a prime number and b\displaystyle b is an integer.
(5)

1.47: In triangle , cm, cm, cm and angle (a) Show that where is a prime number.

4PM1/2/June/2025 — Question 5 · 8 marks

In triangle ABC\displaystyle ABC, AC=12\displaystyle AC = 12 cm, BC=14\displaystyle BC = 14 cm, AB=x\displaystyle AB = x cm and angle ABC=30\displaystyle ABC = 30^\circ
(a) Show that x=P3±95\displaystyle x = P\sqrt{3} \pm \sqrt{95} where P\displaystyle P is a prime number.
(5)
(b) Hence or otherwise, find in cm2\displaystyle \mathrm{cm}^2, the difference between the two possible areas of triangle ABC\displaystyle ABC
Give your answer in the form mn\displaystyle m\sqrt{n} where m\displaystyle m is a prime number and n\displaystyle n is an integer.
(3)

1.48: Past-paper question 11

4PM1/2/June/2025 — Question 11 · 15 marks

(a) Show that cos4θsin4θ=cos2θ\displaystyle \mathrm{cos}^4 \theta - \mathrm{sin}^4 \theta = \mathrm{cos} 2\theta
(4)
(b) Hence, or otherwise, solve the equation
8cos2(2θ+π4)3=2cos4(θ+π8)2sin4(θ+π8)for0θ<π8 \mathrm{cos}^2 \left( 2\theta + \frac{\pi}{4} \right) - 3 = 2 \mathrm{cos}^4 \left( \theta + \frac{\pi}{8} \right) - 2 \mathrm{sin}^4 \left( \theta + \frac{\pi}{8} \right) \quad \mathrm{for} 0 \leq \theta < \pi
Give your solutions to 2 decimal places.
(7)
(c) Using calculus, find the exact value of π16π8(cos42xsin42x8sin4x)dx\displaystyle \int_{\frac{\pi}{16}}^{\frac{\pi}{8}} (\mathrm{cos}^4 2x - \mathrm{sin}^4 2x - 8 \mathrm{sin} 4x) \mathrm{d}x
Give your answer in the form ab2\displaystyle a - b\sqrt{2} where a\displaystyle a and b\displaystyle b are rational numbers.
(4)

1.54: Past-paper question 11

4PM1/2/November/2025 — Question 11 · 11 marks

1.54 diagram 1
Figure 4 shows a right pyramid ABCDE\displaystyle ABCDE with
• vertex E\displaystyle E
• horizontal square base ABCD\displaystyle ABCD of side 6cm
EA=EB=EC=ED=12\displaystyle EA = EB = EC = ED = 12 cm
• vertical height of h\displaystyle h cm
(a) Show that h=314\displaystyle h = 3\sqrt{14}
(3)
(b) Find, in degrees to one decimal place, the size of the angle between EB\displaystyle EB and the plane ABCD\displaystyle ABCD
(2)
The midpoint of AE\displaystyle AE is P\displaystyle P and the midpoint of BE\displaystyle BE is Q\displaystyle Q
(c) Find, to the nearest degree, the size of the obtuse angle between the plane EPQ\displaystyle EPQ and the plane PQCD\displaystyle PQCD
(6)

1.49: Past-paper question 3

4PM1/2R/June/2025 — Question 3 · 6 marks

1.49 diagram 1
Figure 1 shows sector OABC\displaystyle OABC of a circle with centre O\displaystyle O and radius 6 cm
The size of angle AOC\displaystyle AOC is θ\displaystyle \theta radians.
The perimeter of sector OABC\displaystyle OABC is (12+π)\displaystyle (12 + \pi) cm
The region shown shaded in Figure 1 is bounded by the arc ABC\displaystyle ABC and the line AC\displaystyle AC
The area of this region is Scm2\displaystyle S \mathrm{cm}^2
Find the exact value of S\displaystyle S
(6)

1.50: Past-paper question 6

4PM1/2R/June/2025 — Question 6 · 6 marks

1.50 diagram 1
Figure 2 shows a right pyramid VABCD\displaystyle VABCD with vertex V\displaystyle V and rectangular base ABCD\displaystyle ABCD
AD=VC=3ABAD = VC = 3AB
Find in degrees, to one decimal place, the size of the angle between the plane CVD\displaystyle CVD and the base ABCD\displaystyle ABCD
(6)

1.30: Past-paper question 1

4PM1/1/June/2024 — Question 1 · 4 marks

In triangle ABC\displaystyle ABC, AB=2x\displaystyle AB = 2x cm, BC=3x\displaystyle BC = 3x cm and AC=4x\displaystyle AC = 4x cm
The area of triangle ABC\displaystyle ABC is 50cm2\displaystyle 50 \mathrm{cm}^2
Find, to 2 decimal places, the value of x\displaystyle x
(4)

1.38: Past-paper question 3

4PM1/1/November/2024 — Question 3 · 5 marks

Triangle ABC\displaystyle ABC is such that
AC=10cmAC = 10 \mathrm{cm}
BC=7cmBC = 7 \mathrm{cm}
angleCAB=25\mathrm{angle} CAB = 25^\circ
Given that angle ABC\displaystyle ABC is obtuse,
find, in cm to one decimal place, the length of AB\displaystyle AB
(5)

1.39: Figure 1 shows a right prism Triangle is a cross section of the prism.

4PM1/1/November/2024 — Question 4 · 6 marks

1.39 diagram 1
Figure 1 shows a right prism ABCDEF\displaystyle ABCDEF
Triangle CDE\displaystyle CDE is a cross section of the prism.
DCE=ABF=90\displaystyle \angle DCE = \angle ABF = 90^\circ
EDC=FAB=40\displaystyle \angle EDC = \angle FAB = 40^\circ
DE=AF=15\displaystyle DE = AF = 15 cm
EF=DA=CB=20\displaystyle EF = DA = CB = 20 cm
Find, in degrees to one decimal place, the size of the angle between the line FD\displaystyle FD and the plane DCBA\displaystyle DCBA
(6)

1.40: Past-paper question 8

4PM1/1/November/2024 — Question 8 · 11 marks

(i) (a) Using a formula given on page 2, show that
tan2A=2tanA1tan2A\mathrm{tan} 2A = \frac{2 \mathrm{tan} A}{1 - \mathrm{tan}^2 A}
(2)
(b) Hence, solve the equation
tanAtan2A=0for0A180\mathrm{tan} A^\circ - \mathrm{tan} 2A^\circ = 0 \quad \mathrm{for} 0 \leq A \leq 180
(5)
(ii) Using a formula given on page 2, solve, giving your solutions as exact values
cos(xπ6)=sinxforπx2π\mathrm{cos}\left(x - \frac{\pi}{6}\right) = \mathrm{sin} x \quad \mathrm{for} -\pi \leq x \leq 2\pi
(4)

1.31: Past-paper question 3

4PM1/1R/June/2024 — Question 3 · 8 marks

1.31 diagram 1
Figure 1 shows triangle ABC\displaystyle ABC where
AB=xcmAC=(x+7)cmBAC=30AB = x \mathrm{cm} \quad AC = (x + 7) \mathrm{cm} \quad \angle BAC = 30^\circ
The area of triangle ABC=36cm2\displaystyle ABC = 36 \mathrm{cm}^2
(a) Show that x=9\displaystyle x = 9
(3)
(b) Find, in cm to 3 significant figures, the length of BC\displaystyle BC
(2)
(c) Find, in degrees to one decimal place, the size of
(i) ABC\displaystyle \angle ABC
(ii) ACB\displaystyle \angle ACB
(3)

1.32: Figure 2 shows the sector of a circle with centre and radius cm.

4PM1/1R/June/2024 — Question 4 · 9 marks

1.32 diagram 1
Figure 2 shows the sector OPQ\displaystyle OPQ of a circle with centre O\displaystyle O and radius r\displaystyle r cm.
OP=OQ=rcmarcPQ=(21r)cmPOQ=θradiansOP = OQ = r \mathrm{cm} \quad \mathrm{arc} PQ = (21 - r) \mathrm{cm} \quad \angle POQ = \theta \mathrm{radians}
The area of the sector is Acm2\displaystyle A \mathrm{cm}^2
(a) Show that A=r2(21r)\displaystyle A = \frac{r}{2}(21 - r)
(3)
The area of the sector must be greater than or equal to 27cm2\displaystyle 27 \mathrm{cm}^2
(b) Find the set of possible values of r\displaystyle r
(4)
(c) Hence write down the set of possible values of θ\displaystyle \theta
(2)

1.33: Past-paper question 3

4PM1/2/June/2024 — Question 3 · 6 marks

1.33 diagram 1
Figure 1 shows the sector AOB\displaystyle AOB of a circle with centre O\displaystyle O and radius 3r\displaystyle 3r cm
A circle with radius r\displaystyle r cm touches OA\displaystyle OA and OB\displaystyle OB and the arc AB\displaystyle AB
Angle AOB\displaystyle AOB is θ\displaystyle \theta radians, where 0<θ<π2\displaystyle 0 < \theta < \frac{\pi}{2}
(a) Find the exact value of θ\displaystyle \theta
(2)
The area of the region shown shaded in Figure 1 is 8π\displaystyle 8\picm2\displaystyle \mathrm{cm}^{2}
(b) Find the value of r\displaystyle r
(4)

1.34: Figure 5 shows a right triangular prism where is a rectangle.

4PM1/2/June/2024 — Question 9 · 15 marks

1.34 diagram 1
Figure 5 shows a right triangular prism ABCDEF\displaystyle ABCDEF where ABCD\displaystyle ABCD is a rectangle.
AF=DEBF=CEAD=FE=BCAB=DC=24cmAF = DE \quad BF = CE \quad AD = FE = BC \quad AB = DC = 24 \mathrm{cm}
ABF=DCE=45BAF=CDE=60\angle ABF = \angle DCE = 45^\circ \quad \angle BAF = \angle CDE = 60^\circ
Using a formula from page 2,
(a) show that sinAFB=2+64(a) \text{ show that } \mathrm{sin} AFB = \frac{\sqrt{2} + \sqrt{6}}{4}
(3)
Without using a calculator,
(b) show that BF=12(326)cm(b) \text{ show that } BF = 12(3\sqrt{2} - \sqrt{6}) \mathrm{cm}
(5)
The angle between the plane AEB\displaystyle AEB and the plane ABCD\displaystyle ABCD is 65\displaystyle 65^\circ
(c) Find, in cm to 2 significant figures, the length of EF(c) \text{ Find, in cm to 2 significant figures, the length of } EF
(3)
(d) Find, in degrees to one decimal place, the size of the angle between the line CF and the plane ABCD(d) \text{ Find, in degrees to one decimal place, the size of the angle between the line } CF \text{ and the plane } ABCD
(4)

1.35: Past-paper question 11

4PM1/2/June/2024 — Question 11 · 16 marks

Using formulae from page 2, show that
(a)(i)cos2A=2cos2A1(a) (i) \mathrm{cos} 2A = 2\mathrm{cos}^2 A - 1
(3)
(ii)sin2A=2sinAcosA(ii) \mathrm{sin} 2A = 2\mathrm{sin} A \mathrm{cos} A
(1)
(b) Show that cos3A=cos3A+3cosA4(b) \text{ Show that } \mathrm{cos}^3 A = \frac{\mathrm{cos} 3A + 3\mathrm{cos} A}{4}
(4)
Hence, or otherwise,
(c) solve, giving exact values in terms of π\displaystyle \pi
8cos3(θ2)6cos(θ2)1=0for0θ2π8\mathrm{cos}^3\left(\frac{\theta}{2}\right) - 6\mathrm{cos}\left(\frac{\theta}{2}\right) - 1 = 0 \quad \mathrm{for} 0 \leq \theta \leq 2\pi
(4)
(d) use algebraic integration to find the exact value of
0π(4cos3θsin2θ)dθ\int_0^{\pi} (4\mathrm{cos}^3 \theta - \mathrm{sin} 2\theta) \, \mathrm{d}\theta
(4)

1.41: Past-paper question 1

4PM1/2/November/2024 — Question 1 · 5 marks

1.41 diagram 1
Figure 1 shows sector ROS\displaystyle ROS of a circle with centre O\displaystyle O and radius 2 cm
The size of angle ROS\displaystyle ROS is θ\displaystyle \theta radians.
The area of sector ROS\displaystyle ROS is π2cm2\displaystyle \frac{\pi}{2} \mathrm{cm}^2
(a) Find the exact value of θ\displaystyle \theta
(2)
The perimeter of sector ROS\displaystyle ROS is Pcm\displaystyle P \mathrm{cm}
(b) Find the exact value of P\displaystyle P
(3)

1.36: Past-paper question 10

4PM1/2R/June/2024 — Question 10 · 13 marks

1.36 diagram 1
Figure 4 shows a right pyramid ABCDV\displaystyle ABCDV
The base of the pyramid is a rectangle where,
AB=DC=2xcmAD=BC=xcmAB = DC = 2x \mathrm{cm} \quad AD = BC = x \mathrm{cm}
The edges VA\displaystyle VA, VB\displaystyle VB, VC\displaystyle VC and VD\displaystyle VD are all of equal length.
The angle between VA\displaystyle VA and ABCD\displaystyle ABCD is 45\displaystyle 45^\circ
(a) Show that VA=102x\displaystyle VA = \frac{\sqrt{10}}{2}x cm
(3)
(b) Find in cm, the exact height of the pyramid in terms of x\displaystyle x
(2)
Find, in degrees to one decimal place,
(c) the size of angle VBA\displaystyle VBA
(2)
(d) the size of the obtuse angle between the plane AVC\displaystyle AVC and the plane BVD\displaystyle BVD
(4)
Given that the volume of the pyramid is 95\displaystyle 9\sqrt{5}cm3\displaystyle \mathrm{cm}^{3}
(e) find the value of x\displaystyle x
(2)

1.37: Past-paper question 11

4PM1/2R/June/2024 — Question 11 · 12 marks

(a) Using a formula on page 2 show that cos2A=2cos2A1\displaystyle \mathrm{cos} 2A = 2 \mathrm{cos}^2 A - 1
(2)
(b) Hence show that (2cos2A1)2=cos4A+12\displaystyle (2 \mathrm{cos}^2 A - 1)^2 = \frac{\mathrm{cos} 4A + 1}{2}
(3)
The curve with equation y=sin2x2+(2cos2x1)22+18\displaystyle y = \frac{\mathrm{sin} 2x}{2} + \frac{(2 \mathrm{cos}^2 x - 1)^2}{2} + \frac{1}{8} has a stationary point P\displaystyle P in the range 0xπ6\displaystyle 0 \leq x \leq \frac{\pi}{6}
(c) Find the exact coordinates of P\displaystyle P
(7)

1.20: Past-paper question 9

4PM1/1/June/2023 — Question 9 · 13 marks

(a) Using the formulae on page 2, show that
(i)cos2A=cos2A+12(i) \mathrm{cos}^2 A = \frac{\mathrm{cos} 2A + 1}{2}
(ii)sin2A=1cos2A2(ii) \mathrm{sin}^2 A = \frac{1 - \mathrm{cos} 2A}{2}
(4)
(b) Show that
(2sinxcosx)(sinx3cosx)=12(cos2x7sin2x+5)(2 \mathrm{sin} x - \mathrm{cos} x)(\mathrm{sin} x - 3 \mathrm{cos} x) = \frac{1}{2} (\mathrm{cos} 2x - 7 \mathrm{sin} 2x + 5)
(5)
y=(2sinxcosx)(sinx3cosx)y = (2 \mathrm{sin} x - \mathrm{cos} x)(\mathrm{sin} x - 3 \mathrm{cos} x)
(c) Solve, for 0x180\displaystyle 0^\circ \leq x \leq 180^\circ the equation, dydx=0\displaystyle \frac{\mathrm{d}y}{\mathrm{d}x} = 0
Give your answers to the nearest whole number.
(4)

1.26: Figure 3 shows a right pyramid with a horizontal square base.

4PM1/1/November/2023 — Question 6 · 11 marks

1.26 diagram 1
Figure 3 shows a right pyramid with a horizontal square base.
AB=BC=CD=DA=xcmAB = BC = CD = DA = x \mathrm{cm}
AV=BV=CV=DV=xcmAV = BV = CV = DV = x \mathrm{cm}
O\displaystyle O is the point of intersection of the diagonals of the base.
The vertex V\displaystyle V of the pyramid is vertically above O\displaystyle O
(a) Show that VO=22xcm\displaystyle VO = \frac{\sqrt{2}}{2}x \mathrm{cm}
(3)
(b) Find, in degrees, the size of the angle AVC\displaystyle AVC
(2)
(c) Find, in degrees to one decimal place, the size of the angle between the plane VAB\displaystyle VAB and the plane VDC\displaystyle VDC
(3)
The volume of the pyramid is 200cm3\displaystyle 200 \mathrm{cm}^3
Given that the volume of a pyramid =13×base area×height\displaystyle = \frac{1}{3} \times \text{base area} \times \mathrm{height}
(d) Find to 3 significant figures, the value of x\displaystyle x
(3)

1.27: Past-paper question 10

4PM1/1/November/2023 — Question 10 · 17 marks

(a) Using formulae on page 2, show that
(i)sin2A=2sinAcosA(i) \mathrm{sin} 2A = 2 \mathrm{sin} A \mathrm{cos} A
(ii)cos2A=2cos2A1(ii) \mathrm{cos} 2A = 2 \mathrm{cos}^2 A - 1
(3)
f(θ)=2tanθ1+tan2θf(\theta) = \frac{2 \mathrm{tan} \theta}{1 + \mathrm{tan}^2 \theta}
(b) Show that f(θ)=sin2θ\displaystyle f(\theta) = \mathrm{sin} 2\theta
(4)
(c) Solve, in radians to 3 significant figures, for π2xπ2\displaystyle -\frac{\pi}{2} \leq x \leq \frac{\pi}{2}, the equation
5tan(x+π6)=[1+tan2(x+π6)][12cos2(x+π6)]5 \mathrm{tan}\left(x + \frac{\pi}{6}\right) = \left[1 + \mathrm{tan}^2\left(x + \frac{\pi}{6}\right)\right] \left[1 - 2 \mathrm{cos}^2\left(x + \frac{\pi}{6}\right)\right]
(6)
(d) Using calculus, find the exact value of
0π2(4tanθ1+tan2θcos5θ+2)dθ\int_0^{\frac{\pi}{2}} \left( \frac{4 \mathrm{tan} \theta}{1 + \mathrm{tan}^2 \theta} - \mathrm{cos} 5\theta + 2 \right) \mathrm{d}\theta
(4)

1.21: Past-paper question 3

4PM1/1R/June/2023 — Question 3 · 9 marks

1.21 diagram 1
Figure 2 shows triangle ABC\displaystyle ABC where
AB=10cm,AC=8cm,BC=xcmandBAC=100AB = 10 \mathrm{cm}, \quad AC = 8 \mathrm{cm}, \quad BC = x \mathrm{cm} \quad \mathrm{and} \quad \angle BAC = 100^\circ
(a) Find, to 3 significant figures, the value of x\displaystyle x
(2)
(b) Find, in degrees to one decimal place, the size of
(i) angle ABC\displaystyle ABC
(3)
(ii) angle ACB\displaystyle ACB
The bisector of angle ABC\displaystyle ABC meets AC\displaystyle AC at the point M\displaystyle M
(c) Find the area, in cm2\displaystyle \mathrm{cm}^2 to 3 significant figures, of triangle BMC\displaystyle BMC.
(4)

1.22: Figure 1 shows a circle, centre , with radius cm.

4PM1/2/June/2023 — Question 3 · 6 marks

1.22 diagram 1
Figure 1 shows a circle, centre O\displaystyle O, with radius r\displaystyle r cm.
The points A\displaystyle A, P\displaystyle P and B\displaystyle B lie on the circle.
The obtuse angle AOB=θ\displaystyle AOB = \theta radians.
The area of the sector APBO\displaystyle APBO, shown shaded, is 372.4cm2\displaystyle 372.4 \mathrm{cm}^2 and the length of the arc APB\displaystyle APB is 53.2cm\displaystyle 53.2 \mathrm{cm}.
Find, to 3 significant figures where appropriate, the value of
(i) r\displaystyle r
(ii) θ\displaystyle \theta
(6)

1.23: Figure 4 shows a right pyramid with vertex and base which is a regular pentagon.

4PM1/2/June/2023 — Question 9 · 6 marks

1.23 diagram 1
Figure 4 shows a right pyramid with vertex V\displaystyle V and base ABCDE\displaystyle ABCDE which is a regular pentagon.
AB=BC=CD=DE=EA=2xcmAB = BC = CD = DE = EA = 2x \mathrm{cm}
VA=VB=VC=VD=VE=3xcmVA = VB = VC = VD = VE = 3x \mathrm{cm}
Find, in degrees to one decimal place, the size of the angle between the plane VBC\displaystyle VBC and the base ABCDE\displaystyle ABCDE
(6)

1.28: Past-paper question 2

4PM1/2/November/2023 — Question 2 · 7 marks

In triangle ABC\displaystyle ABC, AB=3x\displaystyle AB = 3x cm, BC=5x\displaystyle BC = 5x cm and ABC=110\displaystyle \angle ABC = 110^\circ
(a) Find, in degrees to one decimal place, the size of BCA\displaystyle \angle BCA
(4)
The area of triangle ABC\displaystyle ABC is 24cm2\displaystyle 24 \mathrm{cm}^2
(b) Find, to 3 significant figures, the value of x\displaystyle x
(3)

1.29: A logo, , is shown shaded in Figure 2.

4PM1/2/November/2023 — Question 9 · 13 marks

1.29 diagram 1
A logo, AEBCD\displaystyle AEBCD, is shown shaded in Figure 2.
The straight line ABC\displaystyle ABC is the diameter of the semicircle ADC\displaystyle ADC
AEB\displaystyle AEB is an arc of a circle with centre O\displaystyle O
All angles are measured in radians.
BC=2x\displaystyle BC = 2x cm
OA=OB=x\displaystyle OA = OB = x cm
• length of arc AEB=1.8x\displaystyle AEB = 1.8x cm
The perimeter of the logo is P\displaystyle P
(a) Show that P=ax(π+πsin0.9+b)\displaystyle P = ax(\pi + \pi \mathrm{sin} 0.9 + b) where a\displaystyle a and b\displaystyle b are constants to be found.
(7)
Given that x=10\displaystyle x = 10 cm,
(b) find, in cm2\displaystyle \mathrm{cm}^2 to 3 significant figures, the area of the logo.
(6)

1.24: Past-paper question 7

4PM1/2R/June/2023 — Question 7 · 7 marks

1.24 diagram 1
Figure 2 shows part of the curve S\displaystyle S with equation y=(cos3θ+3sin3θ)12\displaystyle y = \left( \mathrm{cos} 3\theta + \sqrt{3} \mathrm{sin} 3\theta \right)^{\frac{1}{2}}
where mθn\displaystyle m \leq \theta \leq n
The curve S\displaystyle S meets the x\displaystyle x-axis at the point with coordinates (m,0)\displaystyle (m, 0) and at the point with coordinates (n,0)\displaystyle (n, 0)
(a) Find the exact value of m\displaystyle m and the exact value of n\displaystyle n
(3)
The finite region R\displaystyle R, shown shaded in Figure 2, is bounded by the curve S\displaystyle S, and the x\displaystyle x-axis in the region mθn\displaystyle m \leq \theta \leq n
The region R\displaystyle R is rotated through 2π\displaystyle 2\pi radians about the x\displaystyle x-axis.
(b) Use calculus to find the exact volume of the solid generated.
(4)

1.25: Past-paper question 11

4PM1/2R/June/2023 — Question 11 · 12 marks

(a) Use a formula on page 2 to show that sin2A=12(1cos2A)\displaystyle \mathrm{sin}^2 A = \frac{1}{2}(1 - \mathrm{cos} 2A)
(3)
(b) Show that sin4x+cos4x=3+cos4x4\displaystyle \mathrm{sin}^4 x + \mathrm{cos}^4 x = \frac{3 + \mathrm{cos} 4x}{4}
(5)
(c) Hence solve, in degrees to one decimal place, the equation
8sin4(θ2)+8cos4(θ2)=5sin(2θ)+6for0θ<1808\mathrm{sin}^4\left(\frac{\theta}{2}\right) + 8\mathrm{cos}^4\left(\frac{\theta}{2}\right) = 5\mathrm{sin}(2\theta) + 6 \quad \mathrm{for} 0^\circ \leq \theta < 180^\circ
(4)

1.1: Area in a rectangle using trigonometry

4PM1/1/June/2022 — Question 3 · 7 marks

1.1 diagram 1
Figure 2 shows a rectangle ABCD\displaystyle ABCD with AB=10cm\displaystyle AB=10\,\mathrm{cm} and AD=15cm\displaystyle AD=15\,\mathrm{cm}. E\displaystyle E is the point inside the rectangle such that DE=13cm\displaystyle DE=13\,\mathrm{cm} and BAE=35\displaystyle \angle BAE=35^\circ.
Given that AED\displaystyle \angle AED is obtuse, find the area, in cm2\displaystyle \mathrm{cm}^2 to one decimal place, of triangle BCE\displaystyle BCE.
(7)

1.2: A sector and a shaded area

4PM1/1R/June/2022 — Question 3 · 6 marks

1.2 diagram 1
Figure 1 shows sector ORS\displaystyle ORS of a circle with centre O\displaystyle O and radius 4cm\displaystyle 4\,\mathrm{cm}. The size of angle ROS\displaystyle ROS is θ\displaystyle \theta radians. The area of sector ORS\displaystyle ORS is 2πcm2\displaystyle 2\pi\,\mathrm{cm}^2.
(a) Find the exact value of θ\displaystyle \theta.
(2)
(b) Find the perimeter, in cm\displaystyle \mathrm{cm} to 3 significant figures, of the sector ORS\displaystyle ORS.
(2)
The point T\displaystyle T lies on OR\displaystyle OR such that OT:TR=1:3\displaystyle OT:TR=1:3. The shaded region is bounded by TR\displaystyle TR, TS\displaystyle TS and the arc RS\displaystyle RS. The area of this region is Acm2\displaystyle A\,\mathrm{cm}^2.
(c) Find the exact value of A\displaystyle A.
(2)

1.3: Exact values involving surds and trigonometry

4PM1/1R/June/2022 — Question 6 · 8 marks

Given that
a+552=11+55,\frac{a+\sqrt{5}}{\sqrt{5}-2}=11+5\sqrt{5},
(a) without using a calculator, find the value of a\displaystyle a.
Show your working clearly.
(2)
Triangle PQR\displaystyle PQR is such that
PR=(x+3)cm,QR=xcm,PR=(x+3)\,\mathrm{cm}, \qquad QR=x\,\mathrm{cm},
QPR=30,PQR=45.\angle QPR=30^\circ, \qquad \angle PQR=45^\circ.
(b) Show that
x=3+32.x=3+3\sqrt{2}.
(3)
Given that
sin105=6+24\mathrm{sin}\,105^\circ=\frac{\sqrt{6}+\sqrt{2}}{4}
and that the area of triangle PQR\displaystyle PQR is Acm2\displaystyle A\,\mathrm{cm}^2,
(c) find the exact value of A\displaystyle A in the form
98(p6+q2+r3+s),\frac{9}{8}\left(p\sqrt{6}+q\sqrt{2}+r\sqrt{3}+s\right),
where p\displaystyle p, q\displaystyle q, r\displaystyle r and s\displaystyle s are integers.
(3)

1.4: Use compound-angle results to find an area

4PM1/1R/June/2022 — Question 10 · 11 marks

1.4 diagram 1
Using suitable results for sin(A+B)\displaystyle \mathrm{sin}\,(A+B) and sin(AB)\displaystyle \mathrm{sin}\,(A-B),
(a) show that
2sin4xcosx=sin5x+sin3x.2\mathrm{sin}\,4x\,\mathrm{cos}\,x=\mathrm{sin}\,5x+\mathrm{sin}\,3x.
(3)
Figure 4 shows a sketch of part of the curve with equation
y=6sin4xcosx.y=6\mathrm{sin}\,4x\,\mathrm{cos}\,x.
(b) Use calculus to find the total area of the regions bounded by the curve and the x\displaystyle x-axis between x=0\displaystyle x=0 and x=π2\displaystyle x=\frac{\pi}{2}.
Give your answer to 3 significant figures.
(8)

1.5: Exact area enclosed by two circles

4PM1/2/June/2022 — Question 4 · 7 marks

1.5 diagram 1
Figure 1 shows two circles, C1\displaystyle C_1 and C2\displaystyle C_2, each with a radius of 6cm\displaystyle 6\,\mathrm{cm}.
The centre of C1\displaystyle C_1 is O1\displaystyle O_1 such that O1\displaystyle O_1 lies on C2\displaystyle C_2. The centre of C2\displaystyle C_2 is O2\displaystyle O_2 such that O2\displaystyle O_2 lies on C1\displaystyle C_1.
The circles intersect at the points A\displaystyle A and B\displaystyle B and enclose the region R\displaystyle R, shown shaded in Figure 1.
The area of region R\displaystyle R is Pcm2\displaystyle P\,\mathrm{cm}^2.
Find the exact value of P\displaystyle P, giving your answer in the form
aπbc,a\pi-b\sqrt{c},
where a\displaystyle a, b\displaystyle b and c\displaystyle c are integers.
(7)

1.6: Trigonometric identities and equations

4PM1/2/June/2022 — Question 7 · 11 marks

(i) (a) Using a formula from page 2, show that
tan2θ=2tanθ1tan2θ.\mathrm{tan}\,2\theta = \frac{2\mathrm{tan}\,\theta}{1-\mathrm{tan}^2\theta}.
(2)
Given that tan2α=1\displaystyle \mathrm{tan}\,2\alpha=1,
(b) show that
tanα=a±b,\mathrm{tan}\,\alpha=a\pm\sqrt{b},
where a\displaystyle a and b\displaystyle b are integers whose values need to be found.
(3)
(ii) (a) Using formulae from page 2, show that
cos(x30)=sin(x+30)\mathrm{cos}\,(x-30)^\circ=\mathrm{sin}\,(x+30)^\circ
can be written as tanx=1\displaystyle \mathrm{tan}\,x^\circ=1.
(4)
(b) Hence, or otherwise, solve
cos(2y30)=sin(2y+30)\mathrm{cos}\,(2y-30)^\circ=\mathrm{sin}\,(2y+30)^\circ
for 90<y90\displaystyle -90<y\leq90.
(2)

1.7: Angle between a face of a pyramid and its base

4PM1/2R/June/2022 — Question 6 · 6 marks

1.7 diagram 1
Figure 1 shows a right pyramid VABCD\displaystyle VABCD with vertex V\displaystyle V and square base ABCD\displaystyle ABCD. Each of the edges of the pyramid has the same length.
Find the size, in degrees to one decimal place, of the angle between the plane CVD\displaystyle CVD and the base ABCD\displaystyle ABCD.
(6)

1.8: Solve three trigonometric equations

4PM1/2R/June/2022 — Question 7 · 12 marks

Solve
(a) cos(3x15)=32,0x<180,\mathrm{cos}\,(3x-15)^\circ=\frac{\sqrt{3}}{2}, \qquad 0\leq x<180,
(4)
(b) 3tany+4siny=0,180y<180,3\mathrm{tan}\,y^\circ+4\mathrm{sin}\,y^\circ=0, \qquad -180\leq y<180,
giving your answers to one decimal place where appropriate,
(4)
(c) cosθ=3sin2θ1,180θ<180,\mathrm{cos}\,\theta^\circ=3\mathrm{sin}^2\theta^\circ-1, \qquad -180\leq\theta<180,
giving your answers to one decimal place where appropriate.
(4)

1.9: Exact trigonometric values and an addition formula

4PM1/1/June/2021 — Question 2 · 6 marks

Angle α\displaystyle \alpha is acute such that cosα=35\displaystyle \mathrm{cos}\,\alpha=\frac35.
Angle β\displaystyle \beta is obtuse such that sinβ=12\displaystyle \mathrm{sin}\,\beta=\frac12.
(a) Find the exact value of
(i) tanα\displaystyle \mathrm{tan}\,\alpha,
(ii) tanβ\displaystyle \mathrm{tan}\,\beta.
(3)
(b) Hence show that
tan(α+β)=m3nn3+m,\mathrm{tan}(\alpha+\beta)=\frac{m\sqrt3-n}{n\sqrt3+m},
where m\displaystyle m and n\displaystyle n are positive integers whose values are to be found.
(3)

1.10: A sector and tangents to a circle

4PM1/2/June/2021 — Question 3 · 9 marks

1.10 diagram 1
1.10 diagram 2
Figure 1 shows a sector OPQ\displaystyle OPQ of a circle with centre O\displaystyle O. The radius of the circle is 18cm\displaystyle 18\,\mathrm{cm} and the angle POQ\displaystyle POQ is 2π3\displaystyle \frac{2\pi}{3} radians.
(a) Find the length of the arc PQ\displaystyle PQ, giving your answer as a multiple of π\displaystyle \pi.
(2)
Figure 2 shows the sector OPQ\displaystyle OPQ and the kite OPTQ\displaystyle OPTQ. PT\displaystyle PT is the tangent to the circle at P\displaystyle P and QT\displaystyle QT is the tangent at Q\displaystyle Q, such that angle PTQ=α\displaystyle PTQ=\alpha radians.
(b) (i) Find α\displaystyle \alpha in terms of π\displaystyle \pi.
(1)
(ii) Calculate, to 3 significant figures, the area of the region, shown shaded in Figure 2, which is bounded by the arc PQ\displaystyle PQ and the tangents PT\displaystyle PT and QT\displaystyle QT.
(6)

1.11: Solve related trigonometric equations

4PM1/2/June/2021 — Question 10 · 10 marks

(a) Solve the equation
tanx=3for0x<360.\mathrm{tan}\,x^\circ=-3 \qquad \text{for} \qquad 0\leq x<360.
Give your solutions to the nearest whole number.
(3)
Given that
7sin2θ+sinθcosθ=6,7\mathrm{sin}^2\theta+\mathrm{sin}\,\theta\,\mathrm{cos}\,\theta=6,
(b) show that
tan2θ+tanθ6=0.\mathrm{tan}^2\theta+\mathrm{tan}\,\theta-6=0.
(3)
(c) Hence solve the equation
7sin2y+sinycosy=6for0y<360.7\mathrm{sin}^2y^\circ+\mathrm{sin}\,y^\circ\,\mathrm{cos}\,y^\circ=6 \qquad \text{for} \qquad 0\leq y<360.
Give your solutions to the nearest whole number.
(4)

1.12: Angles in a right pyramid

4PM1/1/November/2020 — Question 3 · 9 marks

1.12 diagram 1
Figure 1 shows the right pyramid ABCDE\displaystyle ABCDE. Its base ABCD\displaystyle ABCD is a horizontal rectangle with AD=12cm\displaystyle AD=12\,\mathrm{cm} and CD=16cm\displaystyle CD=16\,\mathrm{cm}. The height ME\displaystyle ME is 14cm\displaystyle 14\,\mathrm{cm}, where M\displaystyle M is the point of intersection of the diagonals of the base. The sloping edges are all of equal length.
(a) Calculate, to 3 significant figures, the length of a sloping edge.
(3)
Calculate, in degrees to one decimal place, the size of
(b) the angle between AE\displaystyle AE and the base,
(3)
(c) the angle between the plane AED\displaystyle AED and the base.
(3)

1.13: Cosine and sine rules in a triangle

4PM1/1/November/2020 — Question 9 · 12 marks

1.13 diagram 1
Figure 3 shows triangle ABC\displaystyle ABC with AB=12cm\displaystyle AB=12\,\mathrm{cm}, BC=6cm\displaystyle BC=6\,\mathrm{cm} and AC=2xcm\displaystyle AC=2x\,\mathrm{cm}. The point D\displaystyle D is the midpoint of AC\displaystyle AC and BD=6cm\displaystyle BD=6\,\mathrm{cm}.
ABD=θ\displaystyle \angle ABD=\theta^\circ and DBC=ϕ\displaystyle \angle DBC=\phi^\circ, where θ0\displaystyle \theta\neq0 and ϕ0\displaystyle \phi\neq0.
(a) Show that
cosADB=x210812x.\mathrm{cos}\,ADB=\frac{x^2-108}{12x}.
(2)
(b) Hence, or otherwise, show that
AC=66cm.AC=6\sqrt6\,\mathrm{cm}.
(4)
(c) Show that
sin(θ+ϕ)=sinϕ.\mathrm{sin}(\theta^\circ+\phi^\circ)=\mathrm{sin}\,\phi^\circ.
(4)
(d) Hence show that
θ=1802ϕ.\theta=180-2\phi.
(2)

1.14: Use a sinusoidal formula

4PM1/1R/November/2020 — Question 1 · 7 marks

Here is a formula
P=3+2sin(3πt8),0t12.P=3+2\mathrm{sin}\left(\frac{3\pi t}{8}\right), \qquad 0\leq t\leq12.
(a) Find the exact value of P\displaystyle P when t=103\displaystyle t=\frac{10}{3}.
(2)
(b) Find
(i) the largest value of P\displaystyle P,
(ii) the smallest value of P\displaystyle P.
(2)
(c) Find the least value of t\displaystyle t for which P=4\displaystyle P=4.
(3)

1.15: A trigonometric identity and a definite integral

4PM1/1R/November/2020 — Question 6 · 7 marks

(a) Show that
sin(A+B)+sin(AB)=2sinAcosB.\mathrm{sin}(A+B)+\mathrm{sin}(A-B)=2\mathrm{sin}\,A\,\mathrm{cos}\,B.
(2)
(b) Hence express 2sin7xcosx\displaystyle 2\mathrm{sin}\,7x\,\mathrm{cos}\,x in the form
sinmx+sinnx,\mathrm{sin}\,mx+\mathrm{sin}\,nx,
where m\displaystyle m and n\displaystyle n are integers, giving the value of m\displaystyle m and the value of n\displaystyle n.
(1)
(c) Use calculus to evaluate
0π46sin7xcosxdx.\int_0^{\frac{\pi}{4}}6\mathrm{sin}\,7x\,\mathrm{cos}\,x\,\mathrm{d}x.
(4)

1.16: Solve trigonometric equations

4PM1/1R/November/2020 — Question 10 · 11 marks

Solve
(a) sin(x+π3)=32,0x2π,\mathrm{sin}\left(x+\frac{\pi}{3}\right)=\frac{\sqrt{3}}{2}, \qquad 0\leq x\leq2\pi,
giving your answers in terms of π\displaystyle \pi,
(3)
(b) 3sinθ+5cosθ=0,360θ360,3\mathrm{sin}\,\theta+5\mathrm{cos}\,\theta=0, \qquad -360^\circ\leq\theta\leq360^\circ,
giving your answers to the nearest degree,
(3)
(c) 1+sin2y=2cos22y,180y0.1+\mathrm{sin}\,2y=2\mathrm{cos}^2 2y, \qquad -180^\circ\leq y\leq0^\circ.
(5)

1.17: Compound-angle identities, equations and integration

4PM1/2/November/2020 — Question 10 · 16 marks

(a) Show that
cos(A+B)+cos(AB)=2cosAcosB.\mathrm{cos}\,(A+B)+\mathrm{cos}\,(A-B)=2\mathrm{cos}\,A\,\mathrm{cos}\,B.
(2)
(b) Hence show that
cosP+cosQ=2cos(P+Q2)cos(PQ2).\mathrm{cos}\,P+\mathrm{cos}\,Q =2\mathrm{cos}\left(\frac{P+Q}{2}\right) \mathrm{cos}\left(\frac{P-Q}{2}\right).
(3)
(c) Solve, for 0θπ2\displaystyle 0\leq\theta\leq\frac{\pi}{2}, the equation
cos5θ+cos7θ=0.\mathrm{cos}\,5\theta+\mathrm{cos}\,7\theta=0.
Give each solution in terms of π\displaystyle \pi.
(4)
(d) Show that
cos8x+2cos6x+cos4x=4cos6xcos2x.\mathrm{cos}\,8x+2\mathrm{cos}\,6x+\mathrm{cos}\,4x =4\mathrm{cos}\,6x\,\mathrm{cos}^2x.
(3)
(e) Use calculus to find the exact value of
0π3cos6xcos2xdx.\int_0^{\frac{\pi}{3}}\mathrm{cos}\,6x\,\mathrm{cos}^2x\,\mathrm{d}x.
(4)

1.18: Length and area in a triangle

4PM1/2R/November/2020 — Question 3 · 8 marks

1.18 diagram 1
Figure 1 shows triangle ABC\displaystyle ABC in which AB=10cm\displaystyle AB=10\,\mathrm{cm} and AC=12cm\displaystyle AC=12\,\mathrm{cm}. The point D\displaystyle D lies on BC\displaystyle BC such that BD=6cm\displaystyle BD=6\,\mathrm{cm}, DC=2cm\displaystyle DC=2\,\mathrm{cm} and AD=xcm\displaystyle AD=x\,\mathrm{cm}.
(a) Show that x=11\displaystyle x=11.
(4)
(b) Find the area, in cm2\displaystyle \mathrm{cm}^2 to 3 significant figures, of triangle ADB\displaystyle ADB.
(4)

1.19: Tangents and the area outside a sector

4PM1/2R/November/2020 — Question 5 · 8 marks

1.19 diagram 1
In Figure 2, AB\displaystyle AB and AC\displaystyle AC are tangents to a circle with centre O\displaystyle O and radius rcm\displaystyle r\,\mathrm{cm}.
The points B\displaystyle B and C\displaystyle C lie on the circle so that OBC\displaystyle OBC is a sector of this circle and
BOC=2π3 radians.\angle BOC=\frac{2\pi}{3}\ \text{radians}.
Given that the area of the shaded region is 10cm2\displaystyle 10\,\mathrm{cm}^2, find, to 3 significant figures, the value of r\displaystyle r.
(8)

1.55: Sine Rule and Triangle Area

4PM1/1/June/2019 — Question 3 · 6 marks

In triangle ABC\displaystyle ABC, AC=7cm\displaystyle AC=7\,\mathrm{cm}, BC=10cm\displaystyle BC=10\,\mathrm{cm} and BAC=65\displaystyle \angle BAC=65^\circ.
(a) Find, in degrees to the nearest 0.1\displaystyle 0.1^\circ, the size of ABC\displaystyle \angle ABC.
(3)
(b) Find, in cm2\displaystyle \mathrm{cm}^2 to 3 significant figures, the area of triangle ABC\displaystyle ABC.
(3)

1.56: Sector Area and Perimeter

4PM1/1/June/2019 — Question 4 · 6 marks

1.56 diagram 1
Figure 1 shows a sector OAB\displaystyle OAB of a circle where AOB=θ\displaystyle \angle AOB=\theta radians.
The circle has centre O\displaystyle O and radius 15cm\displaystyle 15\,\mathrm{cm}.
The point C\displaystyle C divides OA\displaystyle OA in the ratio 2:1\displaystyle 2:1 and the point D\displaystyle D divides OB\displaystyle OB in the ratio 2:1\displaystyle 2:1.
The area of the region ABDC\displaystyle ABDC, shown shaded in Figure 1, is 100cm2\displaystyle 100\,\mathrm{cm}^2.
Find
(a) the value of θ\displaystyle \theta,
(3)
(b) the perimeter, in cm\displaystyle \mathrm{cm}, of the region ABDC\displaystyle ABDC.
(3)

1.57: Trigonometric Equations and Identities

4PM1/1/June/2019 — Question 7 · 12 marks

(a) Solve
(3cosθ+5)(5sinθ3)=0(3\cos\theta+5)(5\sin\theta-3)=0
for 0θ<180\displaystyle 0^\circ\leqslant\theta<180^\circ.
Give your answers in degrees to 1 decimal place.
(2)
(b) Show that
8sin(xα)=3sin(x+α)8\sin(x-\alpha)=3\sin(x+\alpha)
can be written in the form
5tanx=11tanα.5\tan x=11\tan\alpha.
(5)
(c) Hence solve
8sin(2y30)=3sin(2y+30)8\sin(2y-30^\circ)=3\sin(2y+30^\circ)
for 0y<180\displaystyle 0^\circ\leqslant y<180^\circ.
Give your answers in degrees to 1 decimal place.
(5)

1.65: Show can be that written the equation in the form a sin(x sin(x a a

4PM1/1/January/2019 — Question 4 · 11 marks

1.65 diagram 1
sin(A+B)=sinAcosB+sinBcosA\sin(A+B)=\sin A\cos B+\sin B\cos A
tanA=sinAcosA\tan A=\frac{\sin A}{\cos A}
(a) Show that the equation
asin(x30)=bsin(x+30)a\sin(x-30)^\circ=b\sin(x+30)^\circ
can be written in the form
tanx=a+b3(ab).\tan x^\circ=\frac{a+b}{\sqrt{3}(a-b)}.
(5)
In triangle ABC\displaystyle ABC, AC=6cm\displaystyle AC=6\,\mathrm{cm}, BC=14cm\displaystyle BC=14\,\mathrm{cm}, ABC=(x30)\displaystyle \angle ABC=(x-30)^\circ and BAC=(x+30)\displaystyle \angle BAC=(x+30)^\circ, as shown in Figure 2.
(b) Find, in degrees to 1 decimal place, the size of ACB\displaystyle \angle ACB.
(4)
(c) Find, to 3 significant figures, the area of triangle ABC\displaystyle ABC.
(2)

1.58: Arc Length and Sector Area

4PM1/1R/June/2019 — Question 1 · 3 marks

1.58 diagram 1
Figure 1 shows sector AOB\displaystyle AOB of a circle with centre O\displaystyle O and radius rcm\displaystyle r\,\mathrm{cm}. The angle AOB\displaystyle AOB is 1.5 radians and the length of arc AB\displaystyle AB is 12cm\displaystyle 12\,\mathrm{cm}.
Calculate
(a) the value of r\displaystyle r,
(1)
(b) the area of the sector AOB\displaystyle AOB.
(2)

1.59: Sine Rule and Triangle Area

4PM1/1R/June/2019 — Question 2 · 6 marks

1.59 diagram 1
Figure 2 shows triangle ABC\displaystyle ABC in which
AB=2x cm,AC=3x cm,BC=4x cm.AB=2x\text{ cm}, \qquad AC=3x\text{ cm}, \qquad BC=4x\text{ cm}.
(a) Show that
sinABC=31516.\sin ABC=\frac{3\sqrt{15}}{16}.
(4)
Given that the area of triangle ABC\displaystyle ABC is
751564 cm2,\frac{75\sqrt{15}}{64}\text{ cm}^2,
(b) find the value of x\displaystyle x.
(2)

1.60: In triangle and angle

4PM1/2/June/2019 — Question 4 · 5 marks

In triangle ABC,AB=5xcm,BC=(3x1)cm,AC=(2x+5)cm\displaystyle ABC, AB = 5x \mathrm{cm}, BC = (3x - 1) \mathrm{cm}, AC = (2x + 5) \mathrm{cm} and angle ABC=60°\displaystyle ABC = 60°
Find, to 3\displaystyle 3 significant figures, the value of x.
(5)

1.61: Angles and Lengths in a Right Pyramid

4PM1/2/June/2019 — Question 11 · 16 marks

1.61 diagram 1
Figure 1 shows a right pyramid with vertex V\displaystyle V and square base ABCD\displaystyle ABCD, of side 16\displaystyle 16 cm.
The size of angle AVC\displaystyle AVC is 90\displaystyle 90^\circ.
(a) Show that the height of the pyramid is 82\displaystyle 8\sqrt2 cm.
(4)
(b) Find, in cm, the length of VA\displaystyle VA.
(3)
(c) Find, in cm, the exact length of the perpendicular from D\displaystyle D onto VA\displaystyle VA.
(3)
Find, in degrees to one decimal place, the size of
(d) the angle between the plane VAB\displaystyle VAB and the base ABCD\displaystyle ABCD,
(3)
(e) the obtuse angle between the plane VAB\displaystyle VAB and the plane VAD\displaystyle VAD.
(3)

1.66: Trigonometry in a Triangular Pyramid

4PM1/2/January/2019 — Question 5 · 10 marks

1.66 diagram 1
Figure 1 shows a triangular pyramid ABCD\displaystyle ABCD where triangle ABC\displaystyle ABC is the base and BD\displaystyle BD is perpendicular to the base.
AB=15 cm,AC=510 cm,BC=5 cm,BD=10 cm.AB=15\text{ cm}, \qquad AC=5\sqrt{10}\text{ cm}, \qquad BC=5\text{ cm}, \qquad BD=10\text{ cm}.
(a) Show that ABC=90\displaystyle \angle ABC=90^\circ.
(2)
(b) Find, in degrees to 1 decimal place, the size of DAC\displaystyle \angle DAC.
(4)
The point X\displaystyle X on AC\displaystyle AC is such that BX\displaystyle BX is perpendicular to AC\displaystyle AC.
(c) Find, in degrees to 1 decimal place, the size of DXB\displaystyle \angle DXB.
(4)

1.67: Trigonometric Identities and Integration

4PM1/2/January/2019 — Question 11 · 17 marks

cos(A+B)=cosAcosBsinAsinB.\cos(A+B)=\cos A\cos B-\sin A\sin B.
(a)
(i) Using the above identity, show that
cos2x=12sin2x.\cos 2x=1-2\sin^2x.
(ii) Hence show that
13sinx2cos2x104sinx3=4+sinx.\frac{13\sin x-2\cos 2x-10}{4\sin x-3}=4+\sin x.
(7)
(b) Hence solve, in radians to 3 significant figures, the equation
10+2cos(2θ+π3)13sin(θ+π6)=2sin(θ+π6)+810+2\cos\left(2\theta+\frac{\pi}{3}\right)-13\sin\left(\theta+\frac{\pi}{6}\right)=2\sin\left(\theta+\frac{\pi}{6}\right)+8
for πθ2π\displaystyle \pi\leqslant\theta\leqslant2\pi.
(5)
(c) Find the exact value of
0π/2(13sinx2cos2x10+4xsinx3x4sinx3)dx.\int_0^{\pi/2}\left(\frac{13\sin x-2\cos 2x-10+4x\sin x-3x}{4\sin x-3}\right)\,\mathrm{d}x.
(5)

1.62: Lengths and Angles in a Right Prism

4PM1/2R/June/2019 — Question 8 · 13 marks

1.62 diagram 1
Figure 3 shows a right prism ABCDEF\displaystyle ABCDEF. The cross section BCF\displaystyle BCF of the prism is a triangle.
AB=DC=12 cm,BC=AD=8 cm,BF=AE=10 cm,FBC=EAD=60.AB=DC=12\text{ cm}, \qquad BC=AD=8\text{ cm}, \qquad BF=AE=10\text{ cm}, \qquad \angle FBC=\angle EAD=60^\circ.
The point N\displaystyle N lies on BC\displaystyle BC such that FN\displaystyle FN is perpendicular to BC\displaystyle BC.
(a) Show that BN=5\displaystyle BN=5 cm.
(2)
(b) Find, in cm to 3 significant figures, the length of EN\displaystyle EN.
(3)
The midpoint of BF\displaystyle BF is X\displaystyle X and the midpoint of FC\displaystyle FC is Y\displaystyle Y.
(c) Find, in degrees to one decimal place, the size of the angle between the plane ABCD\displaystyle ABCD and the plane AXYD\displaystyle AXYD.
(2)
(d) Find, in degrees to one decimal place, the size of the angle AYE\displaystyle AYE.
(6)

1.63: Multiple-Angle Identities and Integration

4PM1/2R/June/2019 — Question 10 · 15 marks

(a) Use the formula for cos(A+B)\displaystyle \cos(A+B) to show that
cos2A=2cos2A1.\cos 2A=2\cos^2 A-1.
(2)
(b) Show that
cos4A=8cos4A8cos2A+1.\cos 4A=8\cos^4 A-8\cos^2 A+1.
(4)
(c) Solve the equation
cos2(θ4+π24)[cos2(θ4+π24)1]=116,0θ<2π.\cos^2\left(\frac{\theta}{4}+\frac{\pi}{24}\right) \left[\cos^2\left(\frac{\theta}{4}+\frac{\pi}{24}\right)-1\right] =-\frac{1}{16}, \qquad 0\leqslant\theta<2\pi.
Give your answers in terms of π\displaystyle \pi.
(5)
Given that
f(A)=4cos4A4cos2A+1,f(A)=4\cos^4 A-4\cos^2 A+1,
(d) using calculus, find the exact value of
π/6π/2f(A)dA.\int_{\pi/6}^{\pi/2} f(A)\,\mathrm{d}A.
Give your answer in the form aπbc\displaystyle a\pi-b\sqrt{c}, where a\displaystyle a and b\displaystyle b are fractions in their lowest terms and c\displaystyle c is a prime number.
(4)