Question

$frac{-30}{sin^287°+sin^2177°}$

Answer 1

$frac{-30}{sin^287^o+sin^2177^o}=frac{-30}{sin^287^o+sin^2(90^o+87^o)}=frac{-30}{sin^287^o+cos^287^o}=-30;\sin^2x+cos^2x=1$