# Combination of sine functions

#### Benhur

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Summary:
I have the expression sin(2x) + sin(2[x + π/3]) and I have to write this in terms of a single function (a single harmonic, rather saying). But I don't know how to do this, and... it seems a little bit weird for me, because I'm merging two sine-wave functions into one. Doesn't the sum of sines result in a more complex body than a simple sine alone?

The exercise that I'm trying to solve says that I must use a trigonometry formula to solve.

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#### DrClaude

Mentor
The two sines have the same frequency, so it should indeed be possible to write them as a single sinusoidal function.

I suggest you review the basic trigonometric identities to find the one you need:

#### Benhur

Thank you, DrClaude. Now I got it.

#### neilparker62

Homework Helper
Wolfram Alpha sometimes helpful to remind yourself about trig identities: sin(a)+sin(b). (you might have to 'wade' through a lot of extraneous information before you find the required identity)

"Combination of sine functions"

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