Posted by **Sabrina** on Thursday, January 20, 2011 at 11:03am.

a)cos4x-sin4xcot2x=-1

b)1+sinx+cosx/1+sinx-cosx=cot(x/2)

i tried to ask my teacher but she doesnt know please help me!

- math trig identities -
**Sabrina**, Thursday, January 20, 2011 at 12:13pm
Anyone help!!!!!

## Answer This Question

## Related Questions

- Trig........ - I need to prove that the following is true. Thanks (cosx / 1-sinx...
- Pre-Calc - Trigonometric Identities Prove: (tanx + secx -1)/(tanx - secx + 1)= ...
- Precalculus/Trig - I can't seem to prove these trig identities and would really ...
- Trigonometry. - ( tanx/1-cotx )+ (cotx/1-tanx)= (1+secxcscx) Good one! ...
- trigonometry - can i use factoring to simplify this trig identity? the problem ...
- Trigonometry Check - Simplify #3: [cosx-sin(90-x)sinx]/[cosx-cos(180-x)tanx] = [...
- Trigonometry - Prove the following trigonometric identities. please give a ...
- Math - Im really struggling with these proving identities problems can somebody ...
- Mathematics - Trigonometric Identities - Prove: (tanx)(sinx) / (tanx) + (sinx...
- Math - Verify the identity . (cscX-cotX)^2=1-cosX/1+cosX _______ sorry i cant ...

More Related Questions