`"cos" x *"cos" 2x* "cos" 3x` , find d y/ d x

If y = cos x. Cos 2x . Cos 3x find (dy)/(dx)

If y = (cos x)^2 + (x)^cos x , then find dy/dx .

1+ cos 2x+ cos4x + cos 6x= ............. A) 2 cos x cos 2x cos 3x B) 4 sin x cos 2x cos 3x C) 4 cos x cos 2x cos 3x D) 2 sin x cos 2x cos 3x

If y=2sin2x+3cos2x , find (d^2y)/dx^2 .

"Let f(x) "=|{:(cos x" " sin x" " cos x),(cos 2x" "sin 2x" "2cos 2x),(cos 3x" "sin 3x" "3cos 3x):}|" Then find the vlue of "f'(0) and f'(pi//2).

"Let f(x) "=|{:(cos x" " sin x" " cos x),(cos 2x" "sin 2x" "2cos 2x),(cos 3x" "sin 3x" "3cos 3x):}|" Then find the vlue of "f'(0) and f'(pi//2).

x= 2 cos t -cos 2t ,y=2 sin t-sin 2t Find d y / d x

x= 2 cos t -cos 2t ,y=2 sin t-sin 2t Find d y / d x

If y=cos^(-1)x ,find (d^2y)/(dx^2) .

If y=cos^(-1)x ,find (d^2y)/(dx^2) .