# How do i reduce this matrix to echelon form?

• Jul 3rd 2010, 04:42 AM
How do i reduce this matrix to echelon form?
How do i reduce this matrix to echelon form?

http://i50.tinypic.com/20fwz11.jpg

Thanks
• Jul 3rd 2010, 04:56 AM
mr fantastic
Quote:

How do i reduce this matrix to echelon form?

http://i50.tinypic.com/20fwz11.jpg

Thanks

Do row operations. What have you tried? Where are you stuck?
• Jul 3rd 2010, 05:16 AM
Quote:

Originally Posted by mr fantastic
Do row operations. What have you tried? Where are you stuck?

I thought one of the rows had to start with one and make this the top one, but none of them don't?
• Jul 3rd 2010, 05:18 AM
mr fantastic
Quote:

I thought one of the rows had to start with one and make this the top one, but none of them don't?

Are you familiar with the three basic row operations? If so, I don't see what the trouble is.
• Jul 3rd 2010, 05:27 AM
Quote:

Originally Posted by mr fantastic
Are you familiar with the three basic row operations? If so, I don't see what the trouble is.

can you divide the top one by 4?
• Jul 3rd 2010, 03:52 PM
HallsofIvy
Yes, multiplying (or dividing) each number in a row by a fixed number (not dividing by 0, of course) is a row operation.
• Jul 8th 2010, 05:48 AM
Quote:

Originally Posted by HallsofIvy
Yes, multiplying (or dividing) each number in a row by a fixed number (not dividing by 0, of course) is a row operation.

ok so its

1 0 1/4
2 3 -3
2 -1 4
0 1 2

becomes

1 0 1/4
0 3 -7/2
0 -1 7/2
0 1 3/2

• Jul 8th 2010, 02:43 PM
mr fantastic
Quote:

ok so its

1 0 1/4
2 3 -3
2 -1 4
0 1 2

becomes

1 0 1/4
0 3 -7/2
0 -1 7/2
0 1 3/2

Assuming all calculations are correct, it is not quite finished.

I suggest you will benefit by going to your class notes or textbook and reviewing this material more thoroughly.
• Jul 8th 2010, 05:03 PM
HallsofIvy
Well, the first row does start with 1. Now, do the same thing, starting with the second row- you can treat it as if it were a 2 by 3 matrix now.
• Jul 9th 2010, 05:01 AM
Quote:

Originally Posted by mr fantastic
Assuming all calculations are correct, it is not quite finished.

I suggest you will benefit by going to your class notes or textbook and reviewing this material more thoroughly.

How do i do it, can you tell me please.
• Jul 9th 2010, 07:20 PM
mr fantastic
Quote:

How do i do it, can you tell me please.

R4 --> R4 + R3 should be obvious.

As for your notes, that's a reason why educational institutes build libraries ....
• Jul 10th 2010, 05:05 AM
Quote:

Originally Posted by mr fantastic
R4 --> R4 + R3 should be obvious.

As for your notes, that's a reason why educational institutes build libraries ....

So :

1 0 1/4
0 3 -7/2
0 -1 7/2
0 0 5

Is that complete now?
• Jul 10th 2010, 03:38 PM
mr fantastic
Quote: