## AmTran_Bus 3 years ago Trig identities...harder one

1. AmTran_Bus

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2. hba

Try this. First, change all tan(x) and cot(x) into sin(x)/cos(x) and cos(x)/sin(x) respectively. Then combine the fractions using common denominator which is cos(x)sin(x). -Hba.

3. hba

@AmTran_Bus Try it and tell me what you get ?

4. AmTran_Bus

I kept getting it to equal sin2. Let me give it another try.

5. hba

No if you try to reduce it,It will come to $\sin^2x -\cos^2x$

6. AmTran_Bus

Agreed. I see you now. I have it on my paper. But now you have your +2cos^2 on there. I know sin+cos=1 (as long as they are both squared)...but what about the rest?

7. hba

Then put it in the actual ques. $\sin^2x- \cos^2x + 2\cos^2x = 1$

8. hba

Now you know how it goes ? @AmTran_Bus

9. AmTran_Bus

I understand that, yes. But maybe I just can't see it because I can't carry it on.

10. hba

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11. AmTran_Bus

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12. hba

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13. AmTran_Bus

Oh yes. Thanks and Happy Thanksgiving.

14. hba

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