Hey guys, you didn't fail me last time, let's try this again.

1: cos(2X)=cos^4(X)-sin^4(X)

All I've really done on this one is that I factored the ___^4 things, but that didn't really help all that much. Could there possibly be a cos-sin formula involved?

2: csc(2X)-cot(2X) = tan(X)

For this, I did the (hopefully correct) next step of:

((2X)/sin(2x))-((cos(2X)/(sin(2X)) = tan(x)

then I tried this...

(2(x)-cos(2x))/(2sin(x)cos(x))

Is this correct? I'm stuck. please help!

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