Tgt\tgt + ctgt = sin^2t
Tg t/(tg t + Ctg t) = ? a)tg t = Sin t/Cos t б) tg t + Ctg t = Sin t/Cos t + Cos t /Sin t = (Sin² t + Cos ²t)/Cos t Sin t= 1/Cos tSin t в) Sin t/Cos t : 1/Cos tSin t = Sin t /Cos t ·Cos t Sin t /1= Sin²t