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Hi,

Could you please help me decide on these answers?

The question is " Are the following statements Sinusoidal? And are they Periodic?

I have produced the waveforms in MathCad

The limits are 0 - 4Pi

1.f(x)= sinx + 2sin(x-(Pi/6))

2.f(x)= sinx +sin2x

3.f(x)= sinx + 1/2(sin2x)

4.f(x)= sinx + 1/3(sin3x)+1/5(sin5x)

5.f(x)= sinx.cos2x

6.f(x)= sin3x.sin2x

7.f(x)= sin^23x

2. Relevant equations

3. The attempt at a solution

I think they are all periodic as my understanding of periodic is that the waveform repeats itself after 2pi (360 degrees) Which they all seem to do.

I am unsure about the Sinusoidal part though. I know that number 1 is but not sure about the rest!! How do I tell?

I also have to work out the r.m.s value of a complex waveform, Am I right in saying that if its sinusoidal I can use Vmax/root2? If its not sinusoidal can I use this formula?

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# Homework Help: Sinusoidal Waveforms

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