Question

The value

Pi /2
is a solution for the equation 2 sin^2 x- sin x-1=0.
O A. True
B. False

Answer 1

A

Explanation:

Check the solution by substituting x =
`(\pi )/(2)` into the left side of the equation

2sin²x - sinx - 1

= 2sin²(
`(\pi )/(2)` ) - sin (
`(\pi )/(2)` ) - 1

= 2(1)² - 1 - 1

= 2 - 1 - 1

= 0

= right side

`(\pi )/(2)` is therefore a solution to the equation