# Method of undertermined coefficients

#### lordy12

1. The problem statement, all variables and given/known data
The motion of an undamped mass-spring system is described by the differential equation 2x" + 36x = sin(wt)

a) For what values of w will the system exhibit resonance?
b) Use the method of undertermined coefficients to find a particular solution in the case where w is not the resonant frequency.

I know I have to use y = Asin(wt) but I am stuck after that.

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#### ideasrule

Homework Helper
Re: Resonance

Do you know how to solve a second-order differential equation? First you solve the corresponding homogeneous equation, then find a particular solution, then add the two. You may find it easier to do a) after doing b).

"Method of undertermined coefficients"

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