Question 397182
Verify following is an identity.
tan^2(x)+1= (tan(x)/(cos(x))(sin(x))

starting with the right-hand side.
(tan(x)/(cos(x))(sin(x)
=(sin/cos)/(cos)(sin)
=(sin)/(cos^2)(sin)
=1/cos^2
=(sin^2+cos^2)/(cos^2)
=(sin^2/cos^2)+(cos^2/cos^2)
=tan^2+1=left-hand side
verified:right-hand side=left-hand side