Question

cosa-cosb/sina+sinb = если a-b = 90 градусов.

Answer 1

$frac{Cosalpha-Cosbeta}{Sinalpha+Sinbeta }=frac{-2Sinfrac{alpha+ beta }{2}*Sinfrac{alpha-beta}{2}}{2Sinfrac{alpha+beta}{2}*Cosfrac{alpha-beta}{2}}=frac{-Sinfrac{90^{0} }{2} }{Cosfrac{90^{0} }{2} }=frac{-Sin45^{0} }{Cos45^{0} } =frac{-frac{sqrt{2} }{2} }{frac{sqrt{2} }{2}}=-1$

Answer 2

Дай Бог здоровья.

Answer 3

Взаимно ))