I need to get from this:

a^2 / 4*sin(x)*cos(x)

To this:

a^2 * tan(x)

thanks

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- May 17th 2011, 08:31 AMklik11Stuck in this trigonometric equation...
I need to get from this:

a^2 / 4*sin(x)*cos(x)

To this:

a^2 * tan(x)

thanks - May 17th 2011, 08:35 AMTheEmptySet
- May 17th 2011, 08:38 AMklik11
Thanks for the fast answer.

Is 2*a^2 / 4*sin(x)*cos(x)

false too? - May 17th 2011, 08:41 AMTheEmptySet
Just so we are clear is this what you intended in the first post.

$\displaystyle \frac{a^2}{4\sin(x)\cos(x)}=a^2\tan(x)$

you 2nd question does not make sense. An expression cannot be true or false in the first part you wanted to show the above identity was true and it isn't. - May 17th 2011, 09:23 AMklik11
Yes you were right...

Last question for today:

can

a^2 * cos(2x) + a^2 / 2*sin(x)*cos(x)

be

a^2 * tan(x) - May 17th 2011, 09:29 AMTheEmptySet
- May 17th 2011, 09:32 AMklik11
the second one

- May 17th 2011, 09:44 AMTheEmptySet
No what if

$\displaystyle x=\frac{\pi}{4}$

plug that into both equations and see what you get