Question

Which matrix is the product of a 3 × 3 identity matrix and the scalar 3?

Answer 1

it's D on edge

Explanation:

Answer 2

`\left[\begin{array}{ccc}3&0&0\\0&3&0\\0&0&3\end{array}\right]`

Explanation:

In order to find out the resulting matrix, we will have to multiply the identity matric and the scalar 3:

The 3x3 identity matrix is:

`\left[\begin{array}{ccc}1&0&0\\0&1&0\\0&0&1\end{array}\right]`

Multiplying with scalar 3:

`3\left[\begin{array}{ccc}1&0&0\\0&1&0\\0&0&1\end{array}\right]`

The scalar will be multiplied by each element of the matrix.

Multiplying zeros with scalar 3 will give us zero. So the resulting matrix will be:

`\left[\begin{array}{ccc}3*1&0&0\\0&3*1&0\\0&0&3*1\end{array}\right] = \left[\begin{array}{ccc}3&0&0\\0&3&0\\0&0&3\end{array}\right]`

So the resultant matrix will be a scalar matrix with 3 at diagonal positions..