Left Hand Side : sin x + cos x cot x We know that cot x = cos x sin x Therefore sin x + cos x cot x = sin x + cos x ⋅ ( cos x sin x ) = sin x + cos 2 x sin x = sin 2 x + cos 2 x sin x (We know the Trigonometric Identity sin 2 x + cos 2 x = 1 ) = 1 sin x = csc x (Because Cosecant is the reciprocal of Sine) Hence Proved.