If A = beginbmatrix 1 & 2 & 2 \ 2 & 1 & -2 \ c & 2 & b endbmatrix is a matrix satisfying the equation AA^T = 9I, where I is 3 × 3 identity matrix, then the ordered pair (a, b) is equal to

If A = beginbmatrix 1 & 2 & 2 \ 2 & 1 & -2 \ c & 2 & b… — JEE Main 2015 Mathematics PYQ

JEE Main 2015

A = \begin{bmatrix} 1 & 2 & 2 \\ 2 & 1 & -2 \\ c & 2 & b \end{bmatrix}

is a matrix satisfying the equation

AA^T = 9I

, where

I

3 \times 3

identity matrix, then the ordered pair

(a, b)

is equal to

Show answer

Correct option: D

[JEE Main 2015]

Practise Matrices and Determinants the way it is asked

A timed set of real JEE Main Matrices and Determinants questions, graded as the exam grades. No sign-up.