Question

Срочно!! Прошу!!! Пожалуйста!!
Cos(a)cos(b)-cos(a+b) / sin(a)sin(b)-cos(a-b)
(/) — это разделить (дробь)

Answer 1

$frac{cos alpha *cos beta -cos( alpha + beta )}{sin alpha *sin beta -cos( alpha - beta )} = frac{sin alpha *sin beta -(cos alpha *cos beta -sin alpha *sin beta )}{sin alpha *sin beta -(cos alpha *cos beta +sin alpha *sin beta )} =$
$= frac{2sin alpha *sin beta -cos alpha *cos beta }{-cos alpha *cos beta } = frac{2sin alpha *sin beta }{-cos alpha *cos beta } - frac{cos alpha *cos beta }{-cos alpha *cos beta } =-2tg alpha* tg beta +1$