Trig

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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

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