Question

Select the correct answer from the drop-down menu.The answer choices are in the black box.....which one is it?

Answer 1

C and D

Step-by-step explanation

Step 1: Given that:

`C\text{ = }\begin{bmatrix}{2} & 1{} & {} \\ {1} & {}2 & {} \\ {2} & {1} & \end{bmatrix}\text{ and D = }\begin{bmatrix}{\sqrt[]{4}} & 1{} & {} \\ {1} & {}\sqrt[]{4} & {} \\ {\sqrt[]{4}} & {1} & \end{bmatrix}`

Step 2: Simplify matrix D

`\begin{gathered} \text{D = }\begin{bmatrix}{\sqrt[]{4}} & 1{} & {} \\ {1} & {}\sqrt[]{4} & {} \\ {\sqrt[]{4}} & {1} & \end{bmatrix}\text{ = }\begin{bmatrix}{2} & 1{} & {} \\ {1} & {}2 & {} \\ {2} & {1} & \end{bmatrix}\text{ since }\sqrt[]{4}\text{ = 2.} \\ \end{gathered}`

Hence, matrices C and D are equal.