# Second order differential equations

See the attached file.

(Fun) 3. Find the general solution using the method of undetermined coefficients:

y" - 2y' - 3y = t +e^-t

(More Fun) 4. Find the general solution using the method of undetermined coefficients:

y" + 4y = [sin(t)]^2

(Hint: Express sinÂ²t in terms of cos2t)

(Most Fun) 5. Find the general solution using the method of undetermined coefficients:

y" + 2y' + 2y = e^(-x) cosx.

https://brainmass.com/math/calculus-and-analysis/second-order-differential-equations-28846

#### Solution Summary

The solution shows how to use the method of undetermined coefficients. It includes 9 pages with full derivations.

$2.49