math question

Question

prove 1- cos^2 0 = sin 0 cos 0 tan 0 

Answer 1

call the angle "x"

1-cos^2x=sinxcosxtanx

1-cos^2x=sin^2x  (trig identity)

sinxcosxtanx=sinxcosx(sinx/cosx)

sinxcosx(sinx/cosx)=sinxsinx

sinxsinx=sin^2x

both sides equal sin^2x so the identity is proven