Question

What are all the exact solutions of square root2 cosx -1 = 0 for 0 <= x <= 2pi? Give you answer in radians.

Thank you!

Answer 1

pi/4 and 7pi/4

Explanation:

attached

you're welcome :>

Answer 2

Option 2 -
`x=(\pi)/(4),(7\pi)/(4)`

Explanation:

Given : Expression
`√(2)\cos x-1=0` for
`0\leq x\leq 2\pi`

To find : What are all the exact solutions of expression?

Solution :

First we simplify the expression,

`√(2)\cos x-1=0`

`√(2)\cos x=1`

`\cos x=(1)/(√(2))`

The general solution is

`x=(\pi)/(4)+2\pi n,(7\pi)/(4)+2\pi n`

For
`0\leq x\leq 2\pi`

The solution is
`x=(\pi)/(4),(7\pi)/(4)`

Therefore, Option 2 is correct.