Question

The value of cos (270° + θ) cos (90° – θ) – sin (270° – θ) cos θ is ______.

विकल्प

• 0

• – 1

• `1/2`

• 1

Answer 1

The value of cos (270° + θ) cos (90° – θ) – sin (270° – θ) cos θ is 1.

Explanation:

cos (270° + θ) cos (90° – θ) – sin (270° – θ) cos θ

= sin θ . sin θ + cos θ . cos θ

= sin² θ + cos² θ

= 1