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DarrenSJ

Guest

Matrices help

Hi I have some homework for christmas and finding most of it okay, but struggling with some Matrices problems. Can anyone help please or point me in the right direction?

Find matrices A and B if

A+B=   1  0  2
           5  4  -6
           7  3  8
and

A-B=  -5 -4  8
          11 2  0
          -1 7  4

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If A= 3  -2
        4  -2

Find K so that A^2 = KA-2I^2

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and lastly

Use Gaussian Elimination method to solve the following system equations.

X+Y+2Z = 9
2X+4Y-3Z = 1
3X+6Y-5Z = 0

Thanks to anyone that can help, really stuggled with how to solve these.

zetafunc

Moderator

Registered: 2014-05-21

Posts: 2,441

Website

Re: Matrices help

For the first question, how would you solve that system of equations if A + B and A - B were numbers, rather than matrices?

For the second, can you combine all of those terms into a single matrix?

For the last question, do you know how to perform Gaussian elimination?

bobbym

bumpkin

From: Bumpkinland

Registered: 2009-04-12

Posts: 109,606

Re: Matrices help

Hi DarrenSJ;

Find matrices A and B if

This just amounts to solving lots of linear equations.

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