I am emailing a link of this to everyone on the class list every Friday afternoon. If you are not receiving these emails or want to have them sent to another email address feel free to email me at jpmccarthymaths@gmail.ie and I will add you to the mailing list.

## Tutorials

I am going to take attendance from now on particularly at Friday’s tutorial. If there are more than 15 people at a Friday tutorial then the best-attending surplus will be invited to go to the Tuesday tutorial. There were only 14 at today’s tutorial so the BIS are on their own this Tuesday and all of the Bio are to attend their tutorial on Friday.

## Week 1

In week 1 we introduced the idea of a matrix and explored some of the algebra of matrices such as addition, scalar multiplication, transpose and multiplication.

## Week 2

In Week 2 we introduced the idea of the inverse of a matrix. If we want to calculate the inverse of a matrix we do the Gauss-Jordan algorithm. Why the Gauss-Jordan algorithm works is answered in the language of elementary matrices and row operations.

## Next Week

We see how to use matrix inverses to solve simultaneous equations; e.g.

$2x+3y+z=11$

$x+y+z=6$

$4x-y+10z=32$