Prove the identity
{{{matrix(1,3,(1-2Cos^2x)/(Sin(x)*Cos(x)),"=",... (answered by Edwin McCravy)

Prove the identity:

COS 2X-1/1+COS X = 2COS X -... (answered by lwsshak3)

Prove the following identity:... (answered by Edwin McCravy)

verify the identity:... (answered by richard1234)

Please help me with the following question.

Prove this identity:... (answered by Alan3354,josgarithmetic,MathTherapy)

sin^2x - sin^4x = (cos^2)(sin^2x)

sin^2x - (sin^2x)(sin^2x) = (cos^2x)(sin^2x)
sin^2x  (answered by jim_thompson5910)

Sin^4x-cos^4x=1-2cos^2x (answered by Alan3354)

Prove:

1-cot^2x/1+cot^2x=2cos^2-1



I tried this: 
LHS... (answered by Alan3354)