" 7."sin2x,cos3x,sin mx

cos3x-sin2x=0

The value of (2(sin2x+2cos^(2)x-1))/(cos x sin x cos3x+sin3x) is

sin5x cos3x = sin 9x cos7x

Let P(x)=sqrt((cos x+cos2x+cos3x)^(2)+(sin x+sin2x+sin3x)^(2)) then P(x) is equal to

Number of solution(s) of the equation (sin x)/(cos3x)+(sin3x)/(cos3x)+(sin2x)/(cos27x)=0 in the interval (0,(pi)/(4)) is

Prove that (cos3x)/(sin2x sin4x)+(cos5x)/(sin4x sin6x)+(cos7x)/(sin6x sin8x)+(cos9x)/(sin8x sin10x)=(1)/(2)(cos ecx)[cos ec2x-cos ec10x]

Show that: (sin11x sinx+sin7x sin3x)/(cos11x sinx + cos7x sin3x)=tan8x

show that sin x+sin 3x +sin 5x +sin 7x =4 sin 4x cos 2x cos x .

(sin3x + sin x) sin x + (cos3x-cos x) cos x = 0