Question

A)
1 − sin x/
1 + cos x
,

Answer 1

(1-sin(x))/(1+cos(x)) = (csc(x) - 1)(csc(x) - cot(x))

Explanation:

(1 - sin(x)) / (1+cos(x)) =

[ (1-sin(x))/ (1+cos(x)) ] * (1-cos(x))/(1-cos(x)) =

(1-sin(x))(1-cos(x)) / (1 - cos^2(x)) =

(1-sin(x))(1-cos(x)) / (sin^2(x)) =

[ (1-sin(x)) / sin(x) ] * [ (1 - cos(x)) / sin(x) ] =

(csc(x) - 1)(csc(x) - cot(x))