- #1

You are using an out of date browser. It may not display this or other websites correctly.

You should upgrade or use an alternative browser.

You should upgrade or use an alternative browser.

- Thread starter gomes.
- Start date

- #1

- #2

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,577

- 2,218

- #3

- #4

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,577

- 2,218

- #5

gomes.

- 58

- 0

thanks, but how would i integrate u(t+4)e^[t(-1-iw)-4]?

How do i deal with the u(t+4)?

How do i deal with the u(t+4)?

- #6

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,577

- 2,218

What is u(t+4) equal to for t>-4?

- #7

gomes.

- 58

- 0

sorry im really stuck, u(t)?

- #8

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,577

- 2,218

http://www.efunda.com/math/unit_delta/unit_delta.cfm

- #9

- #10

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,577

- 2,218

Well, the first line definitely doesn't equal the second line.

The integrals look okay.

The integrals look okay.

- #11

gomes.

- 58

- 0

- #12

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,577

- 2,218

[tex]u(t) \ne \int_{-\infty}^\infty u(t+4) e^{t(-1-i\omega)-4}\,dt[/tex]

The integral in the second line is fine to calculate the Fourier transform you're looking for, but it's definitely not equal to u(t) as you wrote.

Try the substitution t'=t+4 to evaluate the integral.

- #13

gomes.

- 58

- 0

thanks! got it now

Share:

- Replies
- 1

- Views
- 64

- Last Post

- Replies
- 6

- Views
- 441

- Replies
- 1

- Views
- 239

- Replies
- 2

- Views
- 93

- Replies
- 6

- Views
- 409

- Replies
- 11

- Views
- 602

- Replies
- 2

- Views
- 212

- Replies
- 5

- Views
- 350

- Last Post

- Replies
- 6

- Views
- 600

- Last Post

- Replies
- 8

- Views
- 417