# diff equation last step of the solution

• Jul 11th 2009, 03:58 AM
transgalactic
diff equation last step of the solution
after solving a long diff question i got

0.5*u(t+1)-0.5*u(t-1)

where u(t) is a step function for t>=0 its 1
and t<0 its 0

my expression looks pretty finite to me

how to continue??
• Jul 11th 2009, 07:38 AM
CaptainBlack
Quote:

Originally Posted by transgalactic
after solving a long diff question i got

0.5*u(t+1)-0.5*u(t-1)

where u(t) is a step function for t>=0 its 1
and t<0 its 0

my expression looks pretty finite to me

how to continue??

Continue how, it looks satisfactory to me (at least as a function definition).

Though I would be wary of this as a solution of a differential equation as it has no derivative in the conventional sense at $t=\pm 1$.

CB
• Jul 11th 2009, 09:20 AM
Calculus26
Could you furnish the original question?

It appears the original DE is non-homogeneous with the forcing term
involving delta functions?