Simplifying a Trigonometric Expression

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4=5
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Simplifying a Trigonometric Expression

Postby 4=5 » Fri Jan 07, 2011 10:09 pm UTC

As you probably know the beat frequency of the combination of two sign waves is their greatest common factor.
so naturally I wondered what the beat frequency of an irrational ratio would be.
I found a way of finding a wave that perfectly fit visually but I don't know how to simplify this equation.

sin(ax)sin(bx) + cos(ax)cos(bx) = cos(2cx)
what is the value of c?

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Lukeje
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Re: Simplifying a Trigonometric Expression

Postby Lukeje » Fri Jan 07, 2011 10:22 pm UTC

Have you ever seen the identity [imath]\cos(a-b)=\cos(a)\cos(b) +\sin(a)\sin(b)[/imath]?
(See here for reference).

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4=5
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Re: Simplifying a Trigonometric Expression

Postby 4=5 » Fri Jan 07, 2011 10:25 pm UTC

thank you


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