Question

sin2x-sin4x=0.как решать?:)

Answer 1

sin4x=2sin2xcos2x

sin2x(1-2cos2x)=0

sin2x = 0 or cos 2x = 1/2

 

sin 2x = 0: x=p/2*k, k in Integers

 

cos 2x = 0: 2x = pi/2+pi*n, n in Integers

x=pi/4 + pi*n/2, n in Integers.

 

Ответ: x=p/2*k, k in Integers or x=pi/4 + pi*n/2, n in Integers.