- #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 Dustinsfl
- Start date

- #1

- #2

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,758

- 2,395

What are you confused about?

- #3

Dustinsfl

- 2,285

- 5

I don't know how to do it so I am confused on what to do.

- #4

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,758

- 2,395

- #5

Mark44

Mentor

- 36,681

- 8,678

Last two inner product questions.

The first one I am little confused on and the second one I don't know what to do.

See worked attached.

For the first one, show that <cos(mx), sin(nx)> = 0. Also show that <cos(mx), cos(mx)> = 1 and that <sin(nx), sin(nx)> = 1.

For the second one, you're showing that the "1 norm" is a norm on R

- #6

Dustinsfl

- 2,285

- 5

How can I integrate cos(mx)*sin(nx) when they don't have the same angle?

- #7

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,758

- 2,395

Use a trig identity to rewrite the product of a sine and a cosine.

- #8

Dustinsfl

- 2,285

- 5

For the second problem, I don't know how to start the proof.

- #9

Mark44

Mentor

- 36,681

- 8,678

- #10

Dustinsfl

- 2,285

- 5

- #11

- #12

vela

Staff Emeritus

Science Advisor

Homework Helper

Education Advisor

- 15,758

- 2,395

- #13

Dustinsfl

- 2,285

- 5

If they are integers, then of course sin goes to zero.

- #14

Mark44

Mentor

- 36,681

- 8,678

Can you elaborate on this a bit more? You haven't said quite enough so that I'm not sure I understand what you're talking about. If you have a given integral on one side, and 1/(s - 1) times the same integral on the other side, add -1/(s - 1) times the integral to both sides, and then combine the two integrals using the rules of plain old fractions. At that point you can solve for the integral algebraically.

If that's not what you're talking about, set me straight, please.

Share:

- Replies
- 5

- Views
- 435

- Replies
- 9

- Views
- 337

- Last Post

- Replies
- 15

- Views
- 604

- Last Post

- Replies
- 6

- Views
- 280

- Replies
- 9

- Views
- 1K

- Last Post

- Replies
- 9

- Views
- 945

- Last Post

- Replies
- 6

- Views
- 1K

- Last Post

- Replies
- 4

- Views
- 473

- Last Post

- Replies
- 16

- Views
- 733

- Replies
- 2

- Views
- 410