- #1

vysero

- 134

- 0

My first question is this: does the IVT and FVT only apply to a function given it has a unit step input? For instance, if I graph this function on my calculator I get an exponentially decaying graph that starts at one and goes to zero.

Say my transfer function is H(s) = (s-10)/(s^2 +20s). The limit @ inf is 1.

My second question (is a double): If I plug H(s) into MATLAB with the following code:

Code:

```
>> a = tf([1 -10 ],[1 20 0])
a =
s - 10
----------
s^2 + 20 s
Continuous-time transfer function.
>> step(a)
```

I get a ramp output that starts at zero and decays to -inf with a slope of -1. How can that be if my limit @ inf says the final value should be 1?

also, When I try to figure out the limit @ 0 I get the undefined answer -10/0 so how do I get around that? I don't believe l'hopital's rule applies to undefined forms like division by zero unless its 0/0 right?