Chapter 5.8, Problem 17P

In each of Problems $14$ through $21$, express the total response of the given initial value problem using a convolution integral to represent the forced response:

$y\text{'}\text{'}+y\text{'}+1.25y=1-u_{\pi }\left(t\right);y\left(0\right)=1,y\text{'}\left(0\right)=-1$