How do you simplify (1+cos y)/(1+sec y)?

2 Answers
Aug 5, 2015

(1+cosy)/(1+secy)=cosy

Explanation:

secy=1/cosy, therefore we have:

(1+cosy)/(1+secy)=(cosy/cosy)((1+cosy)/(1+1/cosy))=
cosy((1+cosy)/(1+cosy))=cosy

Aug 6, 2015

Since secy = 1/cosy, you can rewrite this as:

(1+cosy)/(1+(1/cosy))

Thus, multiply through by ((cosy)/(cosy)):

= (cosy+cos^2y)/(cosy+1)

= cosy(cancel((1+cosy)/(cosy+1)))

= color(blue)(cosy)