Target Mathematics

Past-paper practice

Sketching Polynomials: Topic Questions

16 questions with mark schemes.

1.3: Reciprocal curves and asymptotes and curve intersections

4PM1/2/November/2025 — Question 3 · 8 marks

Curve SS has equation y=252x+1y = 2 - \frac{5}{2x+1} where x12x \neq -\frac{1}{2}
(a) Write down an equation of the asymptote to SS that is parallel to
(i) the yy-axis
(ii) the xx-axis
(3)
(b) Find the coordinates of the point where SS crosses
(i) the yy-axis
(ii) the xx-axis
(2)
(c) Using the axes on the page opposite, sketch SS, showing clearly the asymptotes and the coordinates of the points where SS crosses the coordinate axes.
(3)

1.11: Reciprocal curves and asymptotes and curve intersections

4PM1/1/June/2024 — Question 10 · 16 marks

The curve CC has equation y=ax5bxy = \frac{ax - 5}{b - x} where aa and bb are integers and xbx \neq b
One intersection of CC with the coordinate axes is at the point with coordinates (54,0)\left(\frac{5}{4}, 0\right)
The asymptote parallel to the yy-axis has equation x=3x = 3
(a) Find the value of aa and the value of bb
(2)
(b) Sketch CC, showing clearly the asymptotes with their equations and the coordinates of the points of intersection with the coordinate axes.
(5)
The straight line ll with equation 4y7x=k4y - 7x = k has no points of intersection with CC
(c) Show, using algebra, that the range of possible values of kk can be written as
m<k<nm < k < n
where mm and nn are integers to be found.
(9)

1.3: Estimate roots using a graph

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

1.3 diagram 1
Figure 2 shows part of the curve with equation y=x2312xy = \frac{x^2}{3} - \frac{1}{2x} for 4<x<0-4 < x < 0
By drawing a suitable straight line on the grid, obtain estimates, to one decimal place,
of the roots of the equation 4x3+3x236x6=04x^3 + 3x^2 - 36x - 6 = 0 in the interval 4<x<0-4 < x < 0
(4)

1.5: Reciprocal curves and asymptotes

4PM1/2R/June/2024 — Question 7 · 14 marks

1.5 diagram 1
Figure 2 shows a sketch of part of the curve CC with equation
y=x214x+5wherex54y = \frac{x^2 - 1}{4x + 5} \quad \mathrm{where} x \neq -\frac{5}{4}
(a) Write down the equation of the asymptote to CC that is parallel to the yy-axis.
(1)
The line ll is the normal to CC at the point where x=1x = -1
(b) Find an equation of ll
(7)
The line ll meets CC again at the point DD
(c) Find the coordinates of DD
(6)

1.7: Estimate roots using a graph

4PM1/1/June/2023 — Question 3 · 5 marks

1.7 diagram 1
Figure 1 shows part of the curve with equation y=x2+4x2y = \frac{x}{2} + \frac{4}{x^2} in the interval 0.8<x<70.8 < x < 7
By drawing a suitable straight line on the grid, obtain an estimate, to one decimal place, of the roots of the equation 3x312x2+8=03x^3 - 12x^2 + 8 = 0 in the interval 0.8<x<70.8 < x < 7
(5)

1.21: Asymptotes and intercepts of a rational curve

4PM1/1/June/2021 — Question 3 · 10 marks

A curve CC has equation
y=ax3x+5,y=\frac{ax-3}{x+5},
where aa is a constant and x5x\neq-5.
The gradient of CC at the point on the curve where x=2x=2 is 1849\frac{18}{49}.
(a) Show that a=3a=3.
(3)
Hence
(b) write down an equation of the asymptote to CC that is
(i) parallel to the xx-axis,
(ii) parallel to the yy-axis,
(2)
(c) find the coordinates of the point where CC crosses
(i) the xx-axis,
(ii) the yy-axis.
(2)
(d) Sketch the curve CC, showing clearly its asymptotes and the coordinates of the points where CC crosses the coordinate axes.
(3)

1.23: Cubic curves and reciprocal curves and asymptotes

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

1.23 diagram 1
Figure 2 shows the graph of
y=x+5x2y=x+\frac{5}{x^2}
for 1x41\leq x\leq4, drawn on a grid.
(a) By drawing a suitable straight line on the grid, obtain estimates, to one decimal place, for the roots of
x34x2+5=0x^3-4x^2+5=0
in the interval 1x41\leq x\leq4.
(3)
(b) By drawing a suitable straight line on the grid, obtain an estimate, to one decimal place, for the root of
x3x25=0x^3-x^2-5=0
in the interval 1x41\leq x\leq4.
(4)

1.25: Stationary points and sketch of a rational curve

4PM1/2/November/2020 — Question 9 · 18 marks

A curve CC has equation
y=2+4xx22x+1,x12.y=\frac{2+4x-x^2}{2x+1}, \qquad x\neq-\frac12.
(a) Write the equation of CC in the form
ax2+(by4)x+(yc)=0,ax^2+(by-4)x+(y-c)=0,
where aa, bb and cc are integers whose values are to be found.
(3)
(b) Hence show that xx is real when y2y\leq2 and when y3y\geq3.
(4)
(c) Find the coordinates of the stationary points on CC.
(6)
(d) Sketch CC, showing clearly
(i) the exact coordinates of the points where CC crosses the xx-axis,
(ii) the asymptote to CC that is parallel to the yy-axis,
(iii) the coordinates of the stationary points.
(5)

1.14: Expand and solve a cubic equation

4PM1/1/January/2019 — Question 3 · 5 marks

f(x)=(2x+1)(x2+5x3)f(x)=(2x+1)(x^{2}+5x-3)
(a) Show that f(x)=2x3+11x2x3f(x)=2x^{3}+11x^{2}-x-3.
(2)
(b) Hence use algebra to solve the equation 2x3+11x2x3=02x^{3}+11x^{2}-x-3=0.
Give your roots to 3 decimal places where appropriate.
(3)

1.29: Rational curve asymptotes and tangent

4PM1/1/January/2019 — Question 8 · 15 marks

A curve CC has equation
y=5x32x1,x12.y=\frac{5x-3}{2x-1},\qquad x\neq\frac{1}{2}.
(a) Write down an equation of the asymptote to CC that is
(i) parallel to the yy-axis,
(ii) parallel to the xx-axis.
(2)
(b) Find the coordinates of the points of intersection of CC with the coordinate axes.
(2)
(c) Using calculus show that at every point on the curve, the gradient of CC is positive.
(4)
(d) Using the axes on the opposite page, sketch CC, showing clearly the asymptotes and the coordinates of the points of intersection of CC with the coordinate axes.
(3)
The line ll is the tangent to CC at the point on the curve where x=1x=1.
(e) Find an equation of ll, giving your answer in the form y=mx+cy=mx+c.
(4)

1.28: Curve with two asymptotes and intercepts

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

1.28 diagram 1
Figure 1 shows part of the curve SS with equation y=ax+bx+cy=\dfrac{ax+b}{x+c} where aa, bb and cc are integers.
The asymptote to SS that is parallel to the xx-axis has equation y=2y=-2
The asymptote to SS that is parallel to the yy-axis has equation x=3x=-3
The curve crosses the xx-axis at the point with coordinates (4,0)(4,0)
The curve crosses the yy-axis at the point with coordinates (0,p)(0,p) where pp is a rational number.
Find
(i) the value of aa,
(ii) the value of bb,
(iii) the value of cc,
(iv) the value of pp.
(4)

1.16: Estimate roots using a graph

4PM1/1/June/2018 — Question 4 · 6 marks

1.16 diagram 1
Figure 2 shows the graph of y=x12x2y=x-\dfrac1{2x^2} for 0.4x50.4\le x\le5 drawn on a grid.
(a) (i) Express x12x2x-\dfrac1{2x^2} as a single fraction.
(ii) Hence use the graph to obtain, to one significant figure, an estimate for the value of 0.53\sqrt[3]{0.5}. (3)
(b) By drawing a suitable straight line on the grid, find an estimate to 2 significant figures, for the root of the equation
42x+12x2=04-2x+\dfrac1{2x^2}=0
in the interval 0.4x50.4\le x\le5. (3)

1.35: Curve with asymptote

4PM1/1/June/2018 — Question 6 · 7 marks

The curve CC has equation
y=2x4x3,x3y=\dfrac{2x-4}{x-3},\qquad x\ne3
(a) Write down an equation of the asymptote to CC which is parallel to
(i) the xx-axis, (ii) the yy-axis. (2)
(b) Find the coordinates of the point where CC crosses
(i) the xx-axis, (ii) the yy-axis. (2)
(c) Sketch CC, showing clearly the asymptotes and the coordinates of the points where CC crosses the coordinate axes. (3)

1.31: Reciprocal curves and asymptotes

4PM1/1/January/2017 — Question 6 · 6 marks

1.31 diagram 1
Figure 3 shows a sketch of the curve with equation
y=bx+cx+a,xay=\frac{bx+c}{x+a},\qquad x\ne-a
where aa, bb and cc are integers.
The equations of the asymptotes to the curve are x=2x=-2 and y=3y=3.
The curve crosses the yy-axis at (0,3.5)(0,3.5).
(a) Write down the value of aa and the value of bb. (2)
(b) Find the value of cc. (2)
Given that the curve crosses the xx-axis at (s,0)(s,0)
(c) find the value of ss. (2)

1.40: Estimate roots using a graph

4PM1/2/June/2015 — Question 2 · 8 marks

1.40 diagram 1
(a) Complete the table of values for y=x+6x2y=x+\dfrac6{x^2}. Give your answers to 2 decimal places where necessary.
xx1.01.251.51.752.02.252.52.753.0
yy4.173.713.443.543.67
(2)
(b) On the grid opposite, draw the graph of y=x+6x2y=x+\dfrac6{x^2} for 1x31\le x\le3. (2)
(c) By drawing a suitable straight line on the grid, obtain estimates, to 1 decimal place, for the solutions of the equation x33x2+3=0x^3-3x^2+3=0 in the interval 1x31\le x\le3. (4)