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It may be to add and subtract two matrices with the equal number of rows and cols. R = M + N means “addition of two matrices”, M and N. In this case, rij = mij + nij. R = M − N means “subtraction of two matrices”, M and N. In this case, rij = mij − nij [5].

If the quantity of cols in the matrix is identical to the quantity of rows in another matrix, then the two matrices can be multiplied. In this case, if M is a matrix with p × k and N is one with k × q, “the product matrix” of them is a matrix R with p × q. Each element of “the product matrix” R is considered in the way rij = ∑mik × nkj [5].

“Scalar multiplication of a matrix” is defined by multiplying a matrix with a scalar number. If M is a matrix with p × q and β is a scalar number, then R = β × M is a matrix with p × q. In this case, rij = β × mij for each element of the matrix R [5].