4.4 Multiplication of a Matrix by a Number

4.4 Multiplication of a Matrix by a Number
When matrix is multiplied by a number, every element in the matrix is multiplied by the number.

Example:
Given that  A=( 2 4 5 6 )  , find each of the following.
(a) 3A
(b) -2A 

Solution:
(a) 3A=3( 2 4 5 6 ) =( 3×(2) 3×4 3×5 3×(6) ) =( 6 12 15 18 )


(b) 2A=2( 2 4 5 6 ) =( 2×(2) 2×4 2×5 2×(6) ) =( 4 8 10 12 )