# Trig

posted by
**Jasmine** on
.

Please help with this one. I've worked it out in so many ways and can't tell what's correct.

sinA sinA

----- - ------

1+sinA 1-sinA

Which answer is correct for the problem above?

a) 1+cotA

b) sinA tanA

c) -2tan^2A

d) secA cscA

common denominator: 1-sin^2 A

and that is equal to cos^2 A.

Numerator:

sinA-sin^2A - sinA -sin^2 A

-2sin^2 A

The result:

-2sin^2A /cos^2 A and you recall that tan u= sinU/cosU