Submatrix of A

**Esthephane** · March 4th 2011, 12:28 AM

If A =1 3 -1 2
2 1 0 1
3 2 3 2
4 1 4 1

write down the (3,3)-submatrix of A.

How do i start this? Can't figure it out.

**girdav** · March 4th 2011, 12:53 AM

What is your definition of submatrix?

**Esthephane** · March 4th 2011, 01:08 AM

Honestly, I have no clue. If you could walk me step by step, i'd get it. (obvious)

**FernandoRevilla** · March 4th 2011, 01:42 AM

Originally Posted by Esthephane

Honestly, I have no clue. If you could walk me step by step, i'd get it. (obvious)

Look here .

**Esthephane** · March 4th 2011, 01:45 AM

So mu submatrix of (3,3) would be:

132
211
411
?

**FernandoRevilla** · March 4th 2011, 02:18 AM

Right.

**Esthephane** · March 4th 2011, 02:23 AM

Thanks! Now one last question, how would i be able to compute the (1,3) minor of A?

**FernandoRevilla** · March 4th 2011, 02:30 AM

$\begin{vmatrix}{3}&{-1}&{2}\\{1}&{\;\;0}&{1}\\{1}&{\;\;4}&{1}\end{vmatr ix}=\ldots$

**Esthephane** · March 4th 2011, 02:32 AM

Silly me. thanks man!

**FernandoRevilla** · March 4th 2011, 02:35 AM

Originally Posted by Esthephane

Silly me.

I don't agree.

man!

I agree.

Thread: Submatrix of A