Matrix question. write the detailed formula and explanation/definition of how you did this, .
a=131 232 b= \bigl(\begin{smallmatrix} 211 \\ 323 \\ 211 \end{smallmatrix}\bigr)
a) what is a+b?
b) what is a x b (a times b) ? what is the multiplication formula for 3*3 matrix? how about the multiplication formula for 2*2 matrix and 4*4 matrix?
c) are a and b invertible? why?

a.A+B can not find out

b.=

=

=

In similar way multiply two matrix of order

c.No,because A is not a square matrix and determinant of B is zero.

Step-by-step explanation:

We are given that two matrix

A=

B=

In matrix A , two rows and 3 columns therefore, the order of matrix

In matrix B, 3 rows and 3 columns therefore, the order of matrix B is

a.A+B can no find because when add two matrix then the order of two matrix should be same .

b.

When we multiply on matrix to other matrix then number of columns of first matrix equals to number of rows of second matrix.

Therefore, number of columns of matrix A is equals to number of rows of matrix B.So, we can multiply

=\times

=

Formula for multiply of matrix of order

Let A and B are square matrix of order

Let A= and B=

=

In similar way we multiply of matrix of order and  matrix multiply of order

Let A  and B are matrix of order

Let

=

In similar way we multiply two matrix of order

C.Matrix A is not a square matrix .Therefore, it is not a invertible matrix.

Therefore, the determinant of B is equal to zero therefore, inverse of matrix B does not exist.

Hence, Both matrix A and B are no invertible.

i think it would be 43 movies that would have to be watched.

step-by-step explanation:

think about it. for the second plan, every month is 8 dollars. 8 x 12= 96. so thats the number for the second plan. now for the first plan, its annual meaning you have to pay 10 dollars every year. so now you have to get an equivalent amount of 86 since 96-10=86. 86 divided by 2 since every movie costs 2$ then you would have to watch 43 movies a year to get the same as the second plan. i really hoped this . have a wonderful day as well!