SOLUTION: verify identinty sec^4x – (tan^4x + sec^2x) = sec^2x · sin^2x

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Question 433310: verify identinty
sec^4x – (tan^4x + sec^2x) = sec^2x · sin^2x
Answer by Alan3354(69443) About Me  (Show Source):
You can put this solution on YOUR website!
sec^4x – (tan^4x + sec^2x) = sec^2x · sin^2x
sec^4x – tan^4x - sec^2x) = sec^2x*sin^2x = sin^2/cos^2
Multiply thru by cos^4 and change to sines & cosines
1 - sin^4 - cos^2 = sin^2cos^2
sin^2 - sin^4 = sin^2cos^2
Divide by sin^2
1 - sin^2 = cos^2
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Always change everything to sines and cosines.