Question

The number of sub matrices (1x2) of a matrix (2x3) is

Answer 1

Answer:

Step-by-step explanation:

Since we have a matrix (2 x 3) and a sub matrix (1 x 2)

This sub matrix is uniquely determined by its leading (left most top) element.

Consider an arbitrary sub matrix A of order 1×(3−1)

From here we can easily say that the leading element can only occupy n x 2 = 2n positions.

Thus there are 2 x 2, i.e, 4 sub matrices of the prescribed order . These sub matrices need not be distinct. For example, if all entries of the given matrix are ones, we get only one distinct sub matrix. But each sub matrix is described by its position (using its leading and last entry). In that sense they are distinct.

Answer 2

Answer:

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Step-by-step explanation:

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