Question

Решить уравнение
2cos^ 2x+sin2x-1=0

Answer 1

2cos^2 x - 1 = cos 2x
cos 2x + sin 2x = 0
√2*(cos 2x*1/√2 + sin 2x*1/√2) = 0
√2*(sin(pi/4)*cos(2x) + cos(pi/4)*sin(2x)) = 0
√2*sin (2x + pi/4) = 0
2x + pi/4 = pi*k
x = -pi/8 + pi/2*k