Chapter 4, Problem 9MCQ

To determine

Tofind:thematrix after adding two other matrix.

Answer to Problem 9MCQ

The option $\text{A}$ is correct option and dimension of resultant matrices is $2\times 2$ .

Explanation of Solution

Given:

  $2\left[\begin{array}{cc}3& 5\\ -6& 0\end{array}\right]+4\left[\begin{array}{cc}9& -1\\ 2& 3\end{array}\right]$ .

Concept used:

Same position of matrix will add up in addition matrix.

  $\left[\begin{array}{cc}\text{a}& \text{b}\\ \text{c}& \text{d}\end{array}\right]\text{+}\left[\begin{array}{cc}\text{e}& \text{f}\\ \text{g}& \text{h}\end{array}\right]\text{=}\left[\begin{array}{cc}\text{a+e}& \text{b+f}\\ \text{c+g}& \text{d+h}\end{array}\right]$

Calculation:

  $2\left[\begin{array}{cc}3& 5\\ -6& 0\end{array}\right]+4\left[\begin{array}{cc}9& -1\\ 2& 3\end{array}\right]$ .

  $\left[\begin{array}{cc}6& 10\\ -12& 0\end{array}\right]+\left[\begin{array}{cc}36& -4\\ 8& 12\end{array}\right]=\left[\begin{array}{cc}42& 6\\ -4& 12\end{array}\right].$

Hence, the option $\text{A}$ is correct option anddimension ofresultant matricesis $2\times 2$ .