LHS = \(\cfrac{1-sin\,\text x\,cos\,\text x}{cos\,\text x(sec\,\text x-cosec\,\text x)}\) x \(\cfrac{sin^2\text x-cos^2\text x}{sin^3\text x+cos^3\text x}\)
We know that
We know that a3 + b3 = (a + b) (a2 + b2 – ab)
We know that sin2x + cos2x = 1.
= sinx
= RHS
Hence proved.