Question

How do you find the general solutions for `sqrt{2}cos2x - 5 = 0`?

Answer 1

Solve `sqrt2.cos 2x - 5 = 0`

Explanation:

`sqrt2.cos 2x = 5`
`cos 2x = 5/1.41 = 3.55`

Impossible, because cos always < +- 1.