Question

Write the value of ${\sec }^2\theta \left(1+\sin \theta \right)\left(1-\sin \theta \right)$. [CBSE 2009]

Answer 1

$$\begin{gathered} {\sec }^2\theta \left(1+\sin \theta \right)\left(1-\sin \theta \right) \\ ={\sec }^2\theta \left(1-{\sin }^2\theta \right) \\ =\frac{1}{{\cos }^2\theta }\times {\cos }^2\theta \\ =1 \end{gathered}$$