Question

Please tell me these 2 questions marked with yellow color

Answer 1

L.H.S
sec A(1- sin A)(sec A + tan A)
=1/cosA(1- Sin A)(1/cos A+ sin A/ cos A)
=(1- Sin A)/cos A)(1+ sin A /Cos A)
=(1- Sin A)(1- Sin A)/cos A × cos A
(1-Sin^2 A)/Cos^2 A
=1
therefore,L.H.S=R.H.S
=cos^2 A/cos^2 A