Question

If cos 62° 40' = x, the value of 1 + sin² 27° 20' is ______.

Options

• 1 + x²

• 1 − x²

• x² − 1

• 1 + x

Answer 1

If cos 62° 40' = x, the value of 1 + sin² 27° 20' is 1 + x².

Explanation:

Given,

⇒ cos 62° 40' = x

⇒ cos (90° − 27° 20') = x

⇒ sin 27° 20' = x

Substituting value of sin 27° 20' in 1 + sin² 27° 20', we get :

⇒ 1 + sin² 27° 20' = 1 + x²