The inverse of matrix N = (begin{vmatrix} 2 & 3 \
1 & 4end{vmatrix}) is
1 & 4end{vmatrix}) is
-
A.
(frac{1}{5}) (begin{vmatrix} 2 & 1 \ 3 & 4end{vmatrix}) -
B.
(frac{1}{5}) (begin{vmatrix} 4 & -3 \ -1 & 2end{vmatrix}) -
C.
(frac{1}{5}) (begin{vmatrix} 2 & -1 \ -3 & 4end{vmatrix}) -
D.
(frac{1}{5}) (begin{vmatrix} 4 & 3 \ 1 & 2end{vmatrix})
Correct Answer: Option B
Explanation
N = [2 3]
N-1 = (frac{adj N}{|N|})
adj N = (begin{vmatrix} 4 & -3 \ -1 & 2 end{vmatrix})
|N| = (2 x4) – (1 x 3)
= 8 – 3
=5
N-1 = (frac {1}{5}) (begin{vmatrix} 4 & -3 \ -1 & 2 end{vmatrix})