Multiplication matrix A by matrix B can be applied if and only if the number of columns of matrix A equal to the number of rows of matrix B. The result matrix dimensions: number of rows equal to the number of rows of matrix A and number of columns equal to the number of columns of matrix B:
A_{n × m} ∙ B_{m × k} = C_{n × k}
Matrices multiplication is noncommutative operation:
A ∙ B ≠ B ∙ A
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