XII Maths Chapter 3. Matrix | Page 9

Multiplication of Matrices by scalar
If it is told that the apple & Orange that Tina , Abdul & Minu has is doubled , then we have to multiply each of these matrices elements by 2 . Here 2 is a scalar quantity .
If A = [ aij ] m × n is a matrix and k is a scalar , then kA is another matrix which is obtained by multiplying each element of A by the scalar k .
The negative of a matrix is denoted by – A . We define – A = (– 1 ) A .
Numerical :
Solution : Solving we get
X = 3 , y = 6 , z = 9 & t = 6
Properties of scalar multiplication of a matrix
If A = [ aij ] & B = [ bij ] be two matrices of same order , say m × n , and k and l are scalars , then
o k ( A + B ) = kA + kB , o ( k + l ) A = k A + l A
Multiplication of 2 matrices Let take scenario where Amit wants to buy 5 eraser 7 pencils & Aditi wants to buy 3 eraser 4 pencils