Mathematics 9709 · AS & A Level · Trigonometry

Trigonometry — practice question

(i)[4]

Prove that $\left(\frac{1}{\cos x} - \tan x\right)^2 = \frac{1 - \sin x}{1 + \sin x}$.

(ii)[3]

Hence solve $\left( \frac{1}{\cos 2x} - \tan 2x \right)^2 = \frac{1}{3}$ for $0 \leq x \leq \pi$.

Worked solution & mark scheme

This 7-mark question has a full step-by-step worked solution and mark scheme. One marking point: Rewrites $\tan$ using sine and cosine

  • Full mark scheme, point by point
  • Step-by-step worked solution
  • Write your answer & get it marked instantly by AI