Target Mathematics

1.10: Secant identity and solving in radians

0606/12/M/J/16 — Question 5 · 7 marks

(i)
Show that (1−cos⁡θ)(1+sec⁡θ)=sin⁡θtan⁡θ(1 - \cos\theta)(1 + \sec\theta) = \sin\theta \tan\theta.
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(ii)
Hence solve the equation (1−cos⁡θ)(1+sec⁡θ)=sin⁡θ(1 - \cos\theta)(1 + \sec\theta) = \sin\theta for 0≤θ≤π0 \le \theta \le \pi radians.
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