Let and let A X = Y, Y= pmatrix 4 -1 2 pmatrix , ; X= pmatrix x y z pmatrix

MATHEMATICS · Single correct · CBSE · Mathematics · Determinants · Determinants

Problem

Let

A^{-1}=\begin{pmatrix} 2 & -1 & 0 \\ 1 & 0 & 1 \\ -3 & 2 & 1 \end{pmatrix}

and let

A X = Y,\qquad Y=\begin{pmatrix} 4 \\ -1 \\ 2 \end{pmatrix},\; X=\begin{pmatrix} x \\ y \\ z \end{pmatrix}.

Find the value of

x

. (a) 8 (b) 9 (c) 7 (d) 6