(a) True. Suppose A is a not a square matrix, with m rows and n columns. Then A² is not defined, because you can't multiply an m×n matrix by another m×n matrix.

(b) False. As an example, consider the matrices

$A_{3\times2} = \begin{bmatrix}1&0\\0&1\\0&0\end{bmatrix}$

$B_{2\times3} = \begin{bmatrix}-1&0&1\\0&0&1\end{bmatrix}$

Then both AB and BA are defined, with

$AB_{3\times3} = \begin{bmatrix}-1&0&1\\0&0&1\\0&0&0\end{bmatrix}$

$BA_{2\times2} = \begin{bmatrix}-1&0\\0&0\end{bmatrix}$

In general, you can multiply any m×n by any n×m matrix.

(c) True. Multiplying a m×n matrix by a n×m matrix always yields a m×m matrix, and multiplying a n×m matrix by a m×n matrix always yields a n×n matrix.

4 0

2 years ago

Slove the evolution 10-i=3

worty [1.4K]

Answer:

ans 7

Step-by-step explanation:

given

10_i=3

10_i_3=0

7=i

i=7

4 0

3 years ago