Question

Which of the following is an identity? Also, please include an explanation.

Answer 1

$cot\theta= \frac{ cos \theta}{ sin \theta } \\ sec\theta = \frac{1}{ cos \theta } \\ \\ \\ sin \theta cot\theta sec\theta \\ = sin \theta \cdot \frac{ cos \theta}{ sin \theta } \cdot \frac{1}{ cos \theta } \\ = \frac{ sin \theta}{ sin \theta } =1$


sinθcotθsecθ = 1