## Trigonometric Identities

I can, for the mort part, understand how to derive and "proof" most of my Identity work, but some of the more complex (in my feeble opinion) problems give me quite a bit of trouble.

Can anyone explain these?

"Use the fundamental identities to simplify to sines and cosines:
tan(^2)x - (csc(^2)x/cot(^2)x) "
Someone told me the answer was (-1) and I had no idea how to get that.

and

"Confirm the Identity:
(sinx)/(1-cosx) + (sinx)/(1+cosx) = 2cscx"

Any explanations would be greatly appreciated! Thanks!

 PhysOrg.com science news on PhysOrg.com >> Heat-related deaths in Manhattan projected to rise>> Dire outlook despite global warming 'pause': study>> Sea level influenced tropical climate during the last ice age
 Blog Entries: 9 Recognitions: Homework Help Science Advisor HINT:Use the definitions of "composite" functions (tan,cotan,sec,csc) and the fundamental identity $$\sin^{2}x+\cos^{2}x=1$$ Daniel.
 Recognitions: Gold Member Science Advisor Staff Emeritus My usual advice is to convert everything into sines and cosines, and clear all denominators.