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HeisenbergW
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Homework Statement
Four waves of equal frequency ω are made to interfere. The amplitudes of the first two waves are equal (A), but those of the other two are equal to 2A. Their phase angles relative to that of the first wave are 0, ∏/3, ∏/4, and 2∏/3. Find the amplitude, frequency and phase angle of the resulting wave.
Hint: Use complex notation
Homework Equations
A wave can be written as Acos(ωt+[itex]\varphi[/itex]) where [itex]\varphi[/itex] is the phase angle, A is the amplitude, and ω is the frequency
The Attempt at a Solution
Adding all the waves together, I get
A[cos(ωt)+cos(ωt+∏/3)+cos(ωt+∏/4)cos(ωt+2∏/3)]
for easy addition, and following the suggested hint, I turn this into complex notation, keeping in mind that only the real values apply to the wave.
A[e(iωt)+e(iωt+∏/3)+e(iωt+∏/4)+e(iωt+2∏/3)]
which turns to
Ae(iωt)[1+e(i∏/3)+e(i∏/4)+e(i2∏/3)]
Now here is where i reach a problem. I am unaware how to add these together to get back to a format where I can identify things like the phase angle of the resulting wave.
If i convert the e's inside the brackets back to their cos and sin forms, and then add up the values i get
Ae(iωt)[(1+2√2)/2+i(3√3+2√2)/2]
which leaves me stumped
Any help is appreciated
Thank you in advance