Sin(3π/2-x)ctg(5π/2+x)
Sin(3π/2-x)ctg(5π/2+x)=-cosx(-tgx)= cosx *sinx/cosx=sinx
sin(3π/2 - x) · ctg(5π/2 + x) =
= - cosx ·(- tgx) = cosx · (sinx/cosx) = sinx