You are Here: Home >< Maths

# Matrices a level further maths

Announcements Posted on
Would YOU be put off a uni with a high crime rate? First 50 to have their say get a £5 Amazon voucher! 27-10-2016
1. Attachment 516637516639Can someone solve this ques and upload the picture of the solution
Attached Images

2. (Original post by ja.19)
Attachment 516637516639Can someone solve this ques and upload the picture of the solution
Which part are you struggling on, and what have you tried?
For the first part the rank is the number of linearly independent rows, or equivalently columns of the matrix.
3. The last part where we have to show that there is no vector that satisfies Ax=(0 2 -1 3)
4. (Original post by ja.19)
The last part where we have to show that there is no vector that satisfies Ax=(0 2 -1 3)
You don't need to show that no such vector can exist, only that it can't have all its coordinates positive.
So you suppose where:
with .
Sub in your values for and obtain a contradiction with the inequalities.
Spoiler:
Show
I got this contradiction that .
5. (Original post by joostan)
You don't need to show that no such vector can exist, only that it can't have all its coordinates positive.
So you suppose where:
with .
Sub in your values for and obtain a contradiction with the inequalities.
Spoiler:
Show
I got this contradiction that .
6. Can you help with part 3
7. (Original post by ja.19)
Can you help with part 3
Well if is the vector . Then you know that if is a vector in the null space then: , so you need to find minimise the magnitude of .

## 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: March 30, 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

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