Popular Science: How does matrix multiplication work? How can we determine whether two matrices can be multiplied? No Determinant

First, determine whether the number of columns in the first matrix is equal to the number of rows in the second matrix. You can continue without any solution.

Traverse the first column of Matrix 2 (the first number is in the front) and then multiply it to the first row of Matrix 1. All the numbers are multiplied and then added, first column of the first row

Then, the second row of Matrix 2 corresponds to the operation, and is multiplied by the first row of Matrix 1 to obtain the second column of the first row of the answer.

Likewise, after the number of columns in Matrix 2 is used up, the number of rows in the multiplication target matrix 1 starts from the first column and goes down one row. Then, a loop is made to obtain all the values in the second row of the answer.

In sequence, which is effective for all multiplication matrices.

Follow-up:

If the number of rows on the front side is more than the number of rows on the back end, and the number of columns does not have much on the back end, how can this problem be solved?

A: The preceding Number of columns must be the same as the following number of rows. Otherwise, the matrix cannot be multiplied. This is the rule for further questioning:

The column on the front edge is equal to the row on the back, but the row on the front edge is more than the row on the back, and there are no rows on the back. How can we find the result?

How do I obtain the result from a matrix of 5*2 and a matrix of 2*4?

Supplementary answer:

5*2, 2*4

The preceding column = The following row, which can be

The resulting matrix must be the number of rows and the number of columns, that is, 5*4

Believe it or not, follow the instructions I gave you.