Question

How do I multiply the matrix `((6, 4, 24),(1, -9, 8))` by 4?

Answer 1

To multiply a matrix by a constant, simply multiply every element within the matrix by that constant. Therefore, in the example provided, multiply each individual entry by 4 to receive your answer.

Multiplying a matrix `A` by a single number, called a scalar, is a fairly straightforward process when compared with multiplying two matrices together. One can choose to represent the scalar as a matrix if one wishes, by using the identity matrix (which serves as the multiplicative identity for matrices) and changing every entry on the main diagonal from 1 to the scalar (in this case 4). This is not usually required; however, it may provide assistance in conceptualizing why scalars work in this manner.