Mathematics 9709 · AS & A Level · Trigonometry

Trigonometry — practice question

It is stated that $3\sin 2\theta = \cos \theta$ where $\theta$ is an angle such that $0^{\circ} < \theta < 90^{\circ}$.
(a)[2]

Find $\sin \theta$ exactly.

(b)[2]

Find $\sec \theta$ exactly.

(c)[2]

Find $\cos 2\theta$ exactly.

Worked solution & mark scheme

This 6-mark question has a full step-by-step worked solution and mark scheme. One marking point: “Use the identity $\sin 2\theta=2\sin\theta\cos\theta$” …

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