Can someone help me with a Trig problem?

Question

The problem reads: solve the equation in the given domain: 0<x<2pi

sin2x = -1

I already have the answer sheet, I just can't figure out how to do it. Could someone show me the process?

Answer 1

sin 2x = -1

Trigonometry table in sin270 = -1

So, sin 2x = sin 270

Then 2x = 270

Divide each side by 2.

x = 135 = 3π/4

Domain is 3π/4.