Practicing Success

Target Exam

CUET

Subject

-- Mathematics - Section B1

Chapter

Matrices

Question:

A square non-singular matrix A satisfies $A^2-A+2I=0$, then $A^{-1} =$

Options:

$I-A$

$\frac{1}{2}(I-A)$

$(I+A)$

$\frac{1}{2}(I+A)$

Correct Answer:

$\frac{1}{2}(I-A)$

Explanation:

We have,

$A^2-A +2I=0$

$⇒A-A^2 = 2I$

$⇒ A (I-A) = 2I ⇒ A\left\{\frac{1}{2}(I-A)\right\}=I ⇒ A^{-1} =\frac{1}{2}(I-A)$