MYTUTOR SUBJECT ANSWERS

496 views

How do I multiply 2 matrices?

To multiply two matrices we need to name them A and B.

If for example we have 2 2X2 square matrices we know this will create a 3rd 2x2 martix

For this example we will use :

A:

2 -1 

3 4 

and B:

5 0

 -2 -2

To multiply these we complete this table:

(1st row of A X 1st column B) |  (1st row A X 2nd column B)

---------------------------------------------------------------------------------------

(2nd row A X 1st column B )| (2nd row A X 2nd     column B)

this therefore gives us :

(2X5)+(-1X-2) | (2X0)+(-1X-3)

-------------------------------------------

(3X5)+(4X2) |  (3X0)+(4X-3)

resulting in the matrix AB= 

12  3

7  -12

if you have trouble with this its easy to remmeber, multiply the rows by the columns

by doing this you can tell what order a matrix will come out as for example

a 2X2 matrix multiplied by a 2X1 matrix will give a 2X1 matrix as you are multiplying the rows of the first by the columns of the second. 

Hope this helped, feel free to ask any questions for futher clarification 

Ciara R. A Level Maths tutor, 13 plus  Maths tutor, IB Maths tutor, 1...

12 months ago

Answered by Ciara, who has applied to tutor A Level Maths with MyTutor


Still stuck? Get one-to-one help from a personally interviewed subject specialist

257 SUBJECT SPECIALISTS

Aisling R. A Level Maths tutor, A Level Chemistry tutor
£24 /hr

Aisling R.

Degree: Chemistry (Bachelors) - Bristol University

Subjects offered:Maths, Chemistry

Maths
Chemistry

“Top tutor from the renowned Russell university group, ready to help you improve your grades.”

£22 /hr

Shreya G.

Degree: Biochemistry with molecular medicine (Bachelors) - Nottingham University

Subjects offered:Maths, Biology+ 1 more

Maths
Biology
-Personal Statements-

“I am a first year undergraduate student at The University Of Nottingham, currently studying Biochemistry with molecular medicine. ”

£24 /hr

Joe C.

Degree: General Engineering (Masters) - Durham University

Subjects offered:Maths, Science+ 2 more

Maths
Science
Physics
Computing

“Masters student at Durham University, ready to help you excel at Maths and Science ”

About the author

£20 /hr

Ciara R.

Degree: Electrical and Electronic Engineering MEng with industrial placement (Masters) - Newcastle University

Subjects offered:Maths, Spanish+ 6 more

Maths
Spanish
Physics
History
Extended Project Qualification
English and World Literature
English Literature
-Personal Statements-

“About Me: I am an Electrical and Electronic Engineering student at Newcastle University. I have a real passion for learning and love to teach and instil this in students too.  I am very patient and have been a dance teacher since I w...”

MyTutor guarantee

You may also like...

Other A Level Maths questions

What is a 'derivative'?

x^2 + y^2 + 10x + 2y - 4xy = 10. Find dy/dx in terms of x and y, fully simplifying your answer.

The expansion of (1+x)^4 is 1 + 4x +nx^2 + 4x^3 + x^4. Find the value of n. Hence Find the integral of (1+√y)^4 between the values 1 and 0 (one top, zero bottom).

How do you find the area between two lines?

View A Level Maths tutors

We use cookies to improve your site experience. By continuing to use this website, we'll assume that you're OK with this. Dismiss

mtw:mercury1:status:ok