Hi

Can someone tell me what should be the next step:

I have tried many ways but cannot seem to get the right answer.

This is what i have done:

2R1-R2 -> R2

3R1-R3 -> R3

P.S

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- July 23rd 2010, 02:57 AMPaymemoneyMAtrix Problem using Guassian Method
Hi

Can someone tell me what should be the next step:

I have tried many ways but cannot seem to get the right answer.

This is what i have done:

2R1-R2 -> R2

3R1-R3 -> R3

P.S - July 23rd 2010, 03:03 AMAckbeet
Well, on a computer, you wouldn't multiply row 2 by 1/6, but when doing things by hand, that's what I would do next. It makes it slightly easier to contemplate the next step of getting a zero in the 3,2 position.

- July 23rd 2010, 03:03 AMAckbeet
These are linear algebra questions! Stop posting these in Advanced Applied Math!

- July 23rd 2010, 04:28 AMPaymemoney
- July 23rd 2010, 04:37 AMAckbeet
The pre-algebra forum is in the Pre-University Math Help forum. I guarantee you that your problems would fit correctly in the University Math Help/Linear and Abstract Algebra subforum.

- July 23rd 2010, 05:52 PMPaymemoney
After multiplying by 1/6 to row 2, i then done the following, however i get stuck again because i end up with:

Do you have any suggestions of what i should do instead?

R3-2R1 -> R3

- July 24th 2010, 02:16 AMAckbeet
Hmm. I double-checked your earlier work, and I think you made a mistake. Your original system is this:

After performing the following elementary row operations, as you suggested:

2R1-R2 -> R2

3R1-R3 -> R3,

I get this:

The reason I thought there was an error, was because the original matrix definitely has a solution, but your simplified matrix after those two row operations was inconsistent. So, at this point, I would divide row 2 by 5. What do you get then? - July 24th 2010, 05:12 AMPaymemoney
This is want i got when i divided by 5:

R3-4R2 -> R3

- July 24th 2010, 05:20 AMyeKciM
yes it's correct :D u always when u get some results just put them in your starting system of equations and see is it solution that u get the right one :D

edit: I apologize, I'm not gonna do that again :D - July 24th 2010, 07:20 AMAckbeet
Concur with yeKciM. Incidentally, yeKciM: on this forum it's considered bad form to use anything but full and correct English. Please don't use chat-lingo or texting abbreviations! Thanks! (For reference, look at Rule #12 here.)