Question

If 4 sin^-1x + 6 cos^-1 x = 3π then x = ______.

Options

• `1/sqrt2`

• `1/2`

• 0

• `- 1/2`

Answer 1

If 4 sin^-1x + 6 cos^-1 x = 3π then x = 0.

Explanation:

We have, `4sin^-1 x + 6 cos^-1 x = 3pi`

`=> 4 sin^-1 x + 6(pi/2 - sin^-1 x) = 3pi`

`=> 4 sin^-1 x + 3pi - 6 sin^-1 x = 3pi`

⇒ - 2 sin^-1 x = 0

⇒ sin^-1 x = 0

⇒ x = sin(0) = 0