# Math Help - more unit step functions...

1. ## more unit step functions...

ok im having a bit of a time solving this problem...

y''-5y'+6y=U(t-1) y(0)=0, y'(0)=1

the Unit step is giving me a problem...can i just make it e^-s and solve it?

any help would be appreciated..

thanks in advance!

2. Originally Posted by slapmaxwell1
ok im having a bit of a time solving this problem...

y''-5y'+6y=U(t-1) y(0)=0, y'(0)=1

the Unit step is giving me a problem...can i just make it e^-s and solve it?

any help would be appreciated..

thanks in advance!
Split the problem in two parts...

a) find the solution of the initial values problem...

... and call $\varphi$ this solution...

b) find the solution of the initial values problem...

Kind regards

$\chi$ $\sigma$

3. Originally Posted by slapmaxwell1
ok im having a bit of a time solving this problem...

y''-5y'+6y=U(t-1) y(0)=0, y'(0)=1

the Unit step is giving me a problem...can i just make it e^-s and solve it?

any help would be appreciated..

thanks in advance!
It looks like you are doing a Laplace transform? Note that
$\mathcal{L} \{ U(t - t_0) \} = \frac{e^{-st_0}}{s}$

Since $t_0 = -1$ what is the sign in the exponential?

-Dan