I'm confused at how to use identities to solve problems such as sin(2theta)sin theta = cosine theta? Another example of a problem would be sin(2 theta) = cosine theta

Can anyone help?

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- Apr 22nd 2010, 01:50 PMmicbal9388help solving identity simple problem
I'm confused at how to use identities to solve problems such as sin(2theta)sin theta = cosine theta? Another example of a problem would be sin(2 theta) = cosine theta

Can anyone help? - Apr 22nd 2010, 02:09 PMpickslides

Maybe try

$\displaystyle \sin 2\theta \sin \theta = \cos\theta$

$\displaystyle 2\sin \theta \cos\theta \sin \theta = \cos\theta$

$\displaystyle 2\sin \theta \sin \theta = 1$

$\displaystyle 2\sin ^2\theta = 1$

$\displaystyle \sin ^2\theta = \frac{1}{2}$

$\displaystyle \sin \theta = \frac{1}{\sqrt{2}}$

Can you finish it from here?