Question

prove the following (sec a + tan a)(1-sin a) = cos a​

Answer 1

Answer:

(sec A+tan A)(1-sinA)

=(1/cos A + sin A/cos A)(1-sinA)

=[(1+sinA)/cosA](1-sinA)

=(1+sinA)(1-sinA)/cosA

=(1-sin^2 A)/cosA

=(cos^2 A)/cos A

=cos A