Question

Можно подробное решение? Заранее спасибо

Answer 1

$frac{Cos beta tg beta }{Sin ^{2} beta } -Ctg beta Cos beta = frac{Cos beta * frac{Sin beta }{Cos beta } }{Sin ^{2} beta }- frac{Cos beta }{Sin beta }*Cos beta = frac{Sin beta }{Sin ^{2} beta } - frac{Cos ^{2} beta }{Sin beta } =$$frac{1}{Sin beta }- frac{Cos ^{2} beta }{Sin beta } = frac{1-Cos ^{2} beta }{Sin beta } = frac{Sin ^{2} beta }{Sin beta } =Sin beta$