Question

If $cose{c}^2\theta .(1+cos\theta ).(1-cos\theta )=\lambda$, then the value of $\lambda$ is :

• A. 0
• B. $co{s}^2\theta$
• C. 1
• D. $-1$

Answer 1

The correct option is C 1

$cose{c}^2\theta (1+\cos \theta )(1-\cos \theta )=\lambda$

$\Rightarrow cose{c}^2\theta (1+{\cos }^2\theta )=\lambda$

$\Rightarrow cose{c}^2\theta .{\sin }^2\theta =\lambda$

$\Rightarrow \lambda =1.$

Hence, the answer is $1.$