Question

упростить выражение sin2a/(sina+cosa)^2-1

Answer 1

$\frac{sin(2x)}{(sin(x)+cos(x))^2-1} = \frac{sin(2x)}{sin^2(x)+2sin(x)cos(x)+cos^2(x)-1} = \frac{sin(2x)}{1+2sin(x)cos(x)-1} =\\= \frac{sin(2x)}{sin(2x)} =1$