Cos4xsin3x+sin4xcos3x=1

Question

Cos4xsin3x+sin4xcos3x=1

Answer 1

Cos4xsin3x+sin4xcos3x=1,sin(3x+4x)=1,
sin7x=1,
7x=(π/2)+(2πk), k∈Z
x=(π/14)+(2πk/7), k∈Z