Solve (1+tan square A)(1-sinA)(1+ sinA)

Answer 1

(1 + tan^2A)(1 -sin^2A)

but (1 - sin^2 A) = cos^2 A

and (cos^2A/cos^2A + sin^2A/cos^2 A)
= 1/cos^2 A
so we have
(1/cos^2 A)(cos^2 A)
which is
1