Prove (cos^2x-sin^2x+sin^4x)/(sin^4x) = cot^4x
Trying to solve csc^4x-2csc^2x+1=cot^4x...this is as far as I got.
is it...\[\frac{ \cos ^{2}x-\sin ^{2}x+\sin ^{4}x }{ \sin ^{4}x }=\cot ^{4}x\]
Yes...unless I made a mistake along the way.
we can start factoring sin^2x...
all expression of (1-sin^2x) = cos^2x....
oops i can't finish it... i have to go, but if you'll just apply identity 1 (my last entry)... you'll arrive at... cos^4x/sin^4x = cot^4x.... i'm sorry i have to go....
Thanks I guess. I know I have to end up a (cosx/sinx)^4
we have a moderator viewing he can finish it....
afk?
ok i'm back... i miss my service....
sorry that you missed it then.
\[\frac{ \cos ^{2}x-\sin ^{2}x(1-\sin ^{2}x) }{ \sin ^{4}x }=\frac{ \cos ^{2}x-\sin ^{2}x \cos ^{2}x }{ \sin ^{4}x }\]
factor out cos^2x....
\[\frac{ \cos ^{2}x(1-\sin ^{2}x) }{ \sin ^{4}x }=\frac{ \cos ^{2}x \cos ^{2}x }{ \sin ^{4}x }=\frac{ \cos ^{4}x }{ \sin ^{4}x }\]
\[\frac{ \cos ^{4}x }{ \sin ^{4}x }=\cot ^{4}x\]
that completes the proof.... :-)
I've been on this for 2 hours :< Thank you very much.
you're welcome... anytime... :)
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