- #1

dmoney123

- 32

- 1

## Homework Statement

y''-y=t-4e^(-t)

## Homework Equations

method of undetermined coefficients

## The Attempt at a Solution

solving for characteristic equation first

y''-y=0

r^2-1=0

c_1e^(-t)+c_2e^(t)

RHS

particular solution

t-4e^(-t)

y_p(t)= At+B+Ce^(-t)

y_pt'(t)=A-Ce^(-t)

y_p''(t)=Ce^(-t)

plug into LHS

Ce^(-t)-At-B-Ce^(-t)=t-4e^(-t)

-A=t

A=-1

B=0

C cancels on the left... I am not sure how to any further?

Thanks