3.22: Integrals with sine and identity

0606/23/M/J/21 — Question 8 · 8 marks

(a)(i)
Find sin(ϕ+π3)dϕ\displaystyle\int \mathrm{sin}\left(\dfrac{\phi + \pi}{3}\right)\,\mathrm{d}\phi.
[2]
(a)(ii)
Find (5sin2θ+5cos2θ)dθ\displaystyle\int\bigl(5\,\mathrm{sin}^{2}\theta + 5\,\mathrm{cos}^{2}\theta\bigr)\,\mathrm{d}\theta.
[2]
(b)
Show that 1e(2x+1x2)dx=3e1e\displaystyle\int_{1}^{\mathrm{e}}\left(\frac{2}{x} + \frac{1}{x^{2}}\right)\mathrm{d}x = \frac{3\mathrm{e} - 1}{\mathrm{e}}.
[4]