# Math Help - Direct Integration

1. ## Direct Integration

Calculate, using direct integration, the value of e^2t
given that s > -2.

and...

e^t = 1/s-1
for s > 1

Any help on how to do this direct integration would be great guys, thank you

3. yes. sorry, i didnt put the laplace sign at the front

4. Originally Posted by tone999
Calculate, using direct integration, the value of e^2t
given that s > -2.

and...

e^t = 1/s-1
for s > 1

Any help on how to do this direct integration would be great guys, thank you
By definition: $LT[f(t)] = \int_0^{+\infty} e^{-st} f(t) \, dt$.

Therefore: $LT\left[ e^{2t} \right] = \int_0^{+\infty} e^{-st} e^{2t} \, dt = \int_0^{+\infty} e^{-t(s-2)} \, dt$.

It's expected you can calculate an improper integral like this one.