Prove the following: cos(3π/2 + x)cos(2π + x)[cot(3π/2 - x) + cot(2π + x)] = 1

LHS = cos(3π/2 + x)cos(2π + x)[cot(3π/2 - x) + cot(2π + x)]
= sinxcosx[tanx + cotx]
= sinxcosx(sin²x + cos²x)/(sinxcosx)
= 1
= RHS
Hence proved