## Fundamental Identities

Trigonometric ratios and functions, the unit circle, inverse trig functions, identities, trig graphs, etc.
lorst789
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Joined: Mon Jul 29, 2013 2:48 pm
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### Fundamental Identities

can everyone help solving my problem i cant understand please any one...

COTx + TANx = 2COSx CSCx - SECx CSCx

i need answer ASAP please

nona.m.nona
Posts: 288
Joined: Sun Dec 14, 2008 11:07 pm
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### Re: Fundamental Identities

i cant understand....

COTx + TANx = 2COSx CSCx - SECx CSCx
What were the instructions? Are you supposed to solve via the use of fundamental trig identities, or is this an identity itself and you are needing to prove it? Which part are you not understanding?

lorst789
Posts: 3
Joined: Mon Jul 29, 2013 2:48 pm
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### Re: Fundamental Identities

i need to prove it.. sorry i forgot to put it

nona.m.nona
Posts: 288
Joined: Sun Dec 14, 2008 11:07 pm
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### Re: Fundamental Identities

Prove:

COTx + TANx = 2COSx CSCx - SECx CSCx
This site offers a lesson on proving trigonometric identities; you may access that lesson here.

The lesson recommends starting with the "messier" side of the equation which, in this case, would be the right-hand side (RHS). Another recommendation is to convert each trigonometric function to its equivalent in sine and cosine. This would create the following:

RHS = 2cos(x)csc(x) - sec(x)csc(x)
RHS = 2cos(x)[1/sin(x)] - [1/cos(x)][1/sin(x)]

Then combine and apply identities, as possible:

RHS = 2[cos(x)/sin(x)] - 1/[cos(x)sin(x)]
RHS = 2cos^2(x)/[cos(x)sin(x)] - 1/[cos(x)sin(x)]
RHS = [2cos^2(x) - 1]/[cos(x)sin(x)]

And so forth. If you are unable to complete this exercise, kindly please reply showing your steps, starting from what has been displayed for you above. Thank you.

lorst789
Posts: 3
Joined: Mon Jul 29, 2013 2:48 pm
Contact:

### Re: Fundamental Identities

Thanks to your answer

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