Question

The value of sin² (90° – θ) [1+ cot² (90°– θ)] is

(a) –1 

(b) 0 

(c) \(\frac12\)

(d) 1

Answer 1

(d) 1

Given exp. = cos² θ [1+ tan² θ] 

= cos² θ . sec² θ = 1

[(∵ sin (90° - θ) = cos θ) (cot (90° - θ) = tan θ)]