Question

cos x (sec x +cos x csc2x)=csc2x

Answer 1

cosx secx=1
cos^2 *csc^2= ctn^2 x
1+ctn^2=csc^2
multipy left by sin^2/sin^2
1/sin^2 (sin^2+cos^2)=
csc^2 = csc^2