You are Here: Home >< Maths

# Help solving this Matrix question

Announcements Posted on
Why bother with a post grad? Are they even worth it? Have your say! 26-10-2016
1. I am pretty sure I know how to do the question just unsure about It's lay out. If someone could solve it and show their working that would help me understand a great deal.

Attached Images

2. For part a:
is the transpose of the matrix . In the transpose of a matrix the rows become the columns and the columns become the rows. Using this idea you should be able to find the transpose.

For part b:
Just find the product - however be careful as matrices are not commutative. i.e.

For part c:
Find the determinant and then do one over the determinant multiplied by a rearranged matrix (do you know how it should be rearranged?).

Hope this helps
3. (Original post by Trackstar)
I am pretty sure I know how to do the question just unsure about It's lay out. If someone could solve it and show their working that would help me understand a great deal.

(a) (i) Simply write down the transpose matrix (I trust you know how). No working or anything needed of course.
(ii) Write out AA^T, i.e. the two matrices next to each other in that order, then it will be best to show some intermediate steps in the multiplication (e.g. showing the adding of the different multiplied parts)
(iii) Trivial (remember that AA^-1 = I and A^-1A = I)
4. (Original post by Cryptokyo)
For part a:
is the transpose of the matrix . In the transpose of a matrix the rows become the columns and the columns become the rows. Using this idea you should be able to find the transpose.

For part b:
Just find the product - however be careful as matrices are not commutative. i.e.

For part c:
Find the determinant and then do one over the determinant multiplied by a rearranged matrix (do you know how it should be rearranged?).

Hope this helps
Awesome got it!
5. (Original post by 13 1 20 8 42)
(a) (i) Simply write down the transpose matrix (I trust you know how). No working or anything needed of course.
(ii) Write out AA^T, i.e. the two matrices next to each other in that order, then it will be best to show some intermediate steps in the multiplication (e.g. showing the adding of the different multiplied parts)
(iii) Trivial (remember that AA^-1 = I and A^-1A = I)
thanks, helped a lot

## Register

Thanks for posting! You just need to create an account in order to submit the post
1. this can't be left blank
2. this can't be left blank
3. this can't be left blank

6 characters or longer with both numbers and letters is safer

4. this can't be left empty
1. Oops, you need to agree to our Ts&Cs to register

Updated: September 11, 2016
TSR Support Team

We have a brilliant team of more than 60 Support Team members looking after discussions on The Student Room, helping to make it a fun, safe and useful place to hang out.

This forum is supported by:
Today on TSR

### University open days

Is it worth going? Find out here

Poll
Useful resources

### Maths Forum posting guidelines

Not sure where to post? Read here first

### How to use LaTex

Writing equations the easy way

### Study habits of A* students

Top tips from students who have already aced their exams