Verified answer

sin(2x) - cos(2x) = 0 => sin(2x) = cos(2x) => tan(2x) = 1

2x = π/4, 5π/4, 9π/4, 13π/4

x = π/8, 5π/8, 9π/8, 13π/8

sin2x=cos2x

u=2x

sinu=cosu

u must be pi/4 and 5pi/4 and 9pi/4 and 13pi/4

since those are u, and we are finding x, solve for x for each of these u's

pi/8, 5pi/8, 9pi/8, 13pi/8

these are all the value in the interval.