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Maria
Sep22-04, 09:33 AM
Can someone please help me with this one?

cos2x = 2 cos x sin x

I need to find 4 angles :uhh:

Zurtex
Sep22-04, 09:38 AM
Within what range of x? And have you checked what I posted to this problem in the other thread?

Maria
Sep22-04, 09:40 AM
within the range of 0, 360

Zurtex
Sep22-04, 09:43 AM
Well this is easily solvable as long as you remember these 2 identities:

\sin 2 \theta \equiv 2 \cos \theta \sin \theta

and:

\tan \theta \equiv \frac{\sin \theta}{\cos \theta}

Maria
Sep22-04, 09:46 AM
I got it right... :rofl: