output result of a transfer function and input

Hi guys ,

is every body know that why when I use u as input:

U=laplace(0.1*exp(2.44*t));

and G=(s^-6)/((s+5)*(s+6)*(s+7));

and Y=G*U

it gives me in inverse laplace of Y, this term exp(2.44)?;!

but when I write this G:(s-2.44)/((s+5)*(s+6)*(s+7));

with the same u,

I have h=ilaplace(H) as exp(-5*t)/20 - exp(-6*t)/10 + exp(-7*t)/20

it doesn't have 2.44 term. and it gives me error of this plot.

syms t
U=laplace(0.1*exp(2.44*t));
syms s
G=(s-2.44)/((s+5)*(s+6)*(s+7));
H=G*U;
h=ilaplace(H);
plot(t,h)