Question

(secA-tanA)2=1-s

inA/1+sinA​

Answer 1

(1 ) 2 = 1- s

2 = 1

.... hope this helps you

Answer 2

$(secA { - tanA})^{2} \\ \\ = ( \frac{1}{cosA} - \frac{sinA}{cosA} ) ^{2} \\ \\ = \frac{( {1 - sinA})^{2} }{ {cos}^{2} A} \\ \\ = \frac{( {1 - sinA})^{2} }{1 - {sin}^{2} A} \\ \\ = \frac{1 - sinA}{1 + sinA}$