Help with trig identity

lilygirl

New member
Joined
Oct 31, 2008
Messages
3
2 csc 2x=(1+tan^2x)/tan x


Ok So I have take the RHS and changed them to cos and sines and then used the half identities but I think I screwed up doing that and am not sure why.

Then I have also turned the RHS into sec^2x/tanx but thats not coming out correctly either.

Could anyone help advise me on what I am doing wrong?
 
lilygirl said:
2 csc 2x=(1+tan^2x)/tan x


Ok So I have take the RHS and changed them to cos and sines and then used the half identities but I think I screwed up doing that and am not sure why.

Then I have also turned the RHS into sec^2x/tanx but thats not coming out correctly either.

Could anyone help advise me on what I am doing wrong?

Please show us your work - so that we understand the problem better.

Is the problem:

2csc(2x)=1+tan2(x)tan(x)\displaystyle 2\cdot csc (2x) \, = \, \frac{1 \, + \, \tan^2(x)}{\tan(x)}

or something else....
 
Sorry, Im still trying to figure out how to put math problems on the computer.

The equation you wrote is the one I am looking for.

I did:

1+tan^2x =
tanx
sec^2x=
tanx
1
(cos^2x)tanx
 
lilygirl said:
Im still trying to figure out how to put math problems on the computer.
A good start might be to read the "Read Before Posting" thread, and follow one or both of the links provided for formatting information.

Thank you.

Eliz.
 
lilygirl said:
Sorry, Im still trying to figure out how to put math problems on the computer.

The equation you wrote is the one I am looking for.

I did:

1+tan^2x =
tanx
sec^2x=
tanx
1
(cos^2x)tanx

sec2(x)tan(x)\displaystyle \frac{sec^2(x)}{tan(x)} \,

=1cos2(x)sin(x)cos(x)\displaystyle = \frac{\frac{1}{\cos^2(x)}}{\frac{\sin(x)}{\cos(x)}}

=1cos(x)sin(x)\displaystyle = \frac{\frac{1}{\cos(x)}}{\sin(x)}

=1cos(x)sin(x)\displaystyle = \frac{1}{\cos(x)\cdot \sin(x)}

=22cos(x)sin(x)\displaystyle = \frac{2}{2\cdot\cos(x)\cdot \sin(x)}

Now continue....
 
Thank you! So I was actually doing it correctly? I just doubt myself sometimes. But thank you again!
 
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