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Reading: chapter 3 from the course text.

Exercises: Problems 3.1-3.9 and 3.11 from the course text.

Problem 3.5 is 2nd order inhomogeneous variable coefficient... so according to what you said in class today we don't know how to find homogeneous solutions, right? Did I miss something? Thanks.....

jde98 wrote:Problem 3.5 is 2nd order inhomogeneous variable coefficient... so according to what you said in class today we don't know how to find homogeneous solutions, right? Did I miss something? Thanks.....

That's correct. So a legitimate answer to the question would be that no method covered in this course (or any course that is a prerequisite for this course) enables you to solve that problem.

It's important to know which problems you can solve and which ones you can't.

I think there is a typo for question 3.11. Shouldn't the second term of the characteristic equation in the problem statement be 2*zeta*wn*lambda. There are two zetas in the second term in the equation in the book. It's page 84.

Matthew Zak

Matt Zak wrote:I think there is a typo for question 3.11. Shouldn't the second term of the characteristic equation in the problem statement be 2*zeta*wn*lambda. There are two zetas in the second term in the equation in the book. It's page 84.

You are right, there should only be one zeta.

I was wondering what we should do with regards to the questions about nonlinear equations (specifically 3.3 and 3.7). None of our methods thus far work with this type of equation, so should we write something similar to what you suggested as an answer for 3.5? Thanks.

benrollin wrote:I was wondering what we should do with regards to the questions about nonlinear equations (specifically 3.3 and 3.7). None of our methods thus far work with this type of equation, so should we write something similar to what you suggested as an answer for 3.5? Thanks.

Actually, you do know how to solve 3.3 and 3.7.