1. ## Piecewise Laplace 3

step(t-1)-6*step(t-3)+9*step(t-5)

but it's wrong!!
help!!

2. Originally Posted by Phyxius117

step(t-1)-6*step(t-3)+9*step(t-5)

but it's wrong!!
help!!
Note as quick check when you evaluate at $t=4$ you get
$f(4)=1-6+0=-5$

Just "turning on" the next part is not enough you need to "turn off" the first part as well.
Let $S(t)$ be the unit step function then

$f(t)=S(t-1)-7S(t-3)+15S(t-5)$

Note to fit the turn on and off analogy from above

$f(t)=S(t-1) - S(t-3)-6S(t-3)+6S(t-5)+9S(t-5)$

When you simplify it is the same as above.