`dim_(x-gt0)(cosx-cos3x)/(x(sin3x-sinx))`

lim_{x\rightarrow 0}(cosx-cos3x)/(x(sin 3x-sinx)) is equal to

(cos^3x-sin^3x)/(cosx-sinx)

Prove that (cos5x - cosx)/(sin5x - 2sin3x + sinx) = cotx

Evaluate int_(0)^(pi)sqrt((cosx+cos2x+cos3x)^(2)+(sinx+sin2x+sin3x)^(2))dx

Evaluate int_(0)^(pi)sqrt((cosx+cos2x+cos3x)^(2)+(sinx+sin2x+sin3x)^(2))dx

Find the sum to n terms of the series (sinx)/(cosx+cos2x)+(sin2x)/(cosx+cos4x)+(sin3x)/(cosx+cos6x)+…

Find the sum to n terms of the series (sinx)/(cosx+cos2x)+(sin2x)/(cosx+cos4x)+(sin3x)/(cosx+cos6x)+…

prove that 1-1/2(sin2x)=(sin^3 x +cos^3 x)/(sinx +cosx)

If f(x) = |{:(cos^(2)x, cosx.sinx, -sin x),(cos x sinx ,sin^(2)x ,cos x),(sinx , -cos x , 0):}| then for all x

If f(x) = |{:(cos^(2)x, cosx.sinx, -sin x),(cos x sinx ,sin^(2)x ,cos x),(sinx , -cos x , 0):}| then for all x