Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Matrices

Question:

$A=\begin{bmatrix} 4 & x+2\\ 2x-3 & x+1 \\ \end{bmatrix}$ is a symmetric matrix, then find x.

Options:

6

5

-4

-5

Correct Answer:

5

Explanation:

For a symmetric matrix $A$ we have $A=A^{t}$. The diagonal entries remain same after transpose and in this case the off diagonal entries are equal so we get

$A=A^{t}⇒x+2=2x-3$

so $x=5$.