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  3. Can someone help me prove this trigonometric identity: tan^2x - sin^2x = tan^2x(sin^2x)
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Dani Khan
Aug 18, 2020

Can someone help me prove this trigonometric identity: tan^2x - sin^2x = tan^2x(sin^2x)

It would be great if you can help me solve from what's on the left to get what's on the right. Tried it a few times but I wasn't getting tan^2x(sin^2x) instead my answers were most likely in either cos^2x or sin^2 but not both divided as it would give me tan. :D

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Ian Fowler
Aug 18, 2020

1) On the LHS convert tan^2(x) to sin^2(x)/cos^2(x)

2) Get a common denominator to subtract sin^2(x)

3) Factor and pay close attention to the Pythagorean Identity cos^s(x) + sin^2(x) = 1

4) That should be enough to get you there.

Dani Khan
Aug 18, 2020

I mean I knew that but this time around i tried it from right to left and it worked! thanks for helping though :D

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Dani Khan
Aug 18, 2020

I mean I knew that but i forgot that u can also solve from the right to left and that's what I did and it worked! thanks for the guidance though :D

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Aneesh Srinivas
Jan 9


Dani Khan
Jan 9

thank you

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