Given the function begin{cases}e^{-t}& text{if } 0leq t<2 0&text{if } 2leq tend{cases}Express f(t) in terms of the shifted unit step function u(t -a)F(t)

Caelan

Caelan

Answered question

2020-11-08

Given the function {etif 0t<20if 2t
Express f(t) in terms of the shifted unit step function u(t -a)
F(t) - ?
Now find the Laplace transform F(s) of f(t)
F(s) - ?

Answer & Explanation

escumantsu

escumantsu

Skilled2020-11-09Added 98 answers

Step 1
Since f(t)=0 for 2t and t<0 so create step function: u(t)u(t2) which will give those zero values.
Thus, f(t)=et[u(t)u(t2)] or f(t)=etu(t)etu(t2)
Step 2
Calculate Laplace transform:
F(s)=f(t)estdt
=(etu(t)etu(t2))estdt
=(etu(t))estdt(etu(t2))estdt
=0e(s+1)tdt2e(s+1)tdt
=1(s+1)e2(s+1)(s+1)
=1e2(s+1)(s+1)
Step 3
Thus, Laplace transform is F(s)=1e2(s+1)(s+1)

Do you have a similar question?

Recalculate according to your conditions!

New Questions in Differential Equations

Ask your question.
Get an expert answer.

Let our experts help you. Answer in as fast as 15 minutes.

Didn't find what you were looking for?