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If AB = C, then what is A2 equal to?

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Detailed Solution

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Concept:

Multiplication of matrices:

  • The number of columns of the 1st matrix must equal the number of rows of the 2nd matrix.
  • The result will have the same number of rows as the 1st matrix, and the same number of columns as the 2nd matrix.
  • To multiply an m × n matrix by an n × p matrix, the n must be the same, and the result is an m × p matrix.

 

Calculation:

Given: AB = C

So, 3x + y = 4   …. (1)

x + 2y = -2       …. (2)

Solving equation 1 and 2, we get

x = 2 and y = -2

Now,

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