If A = [a , ,b],B = [ - b - a] and C = [ l , , , ,a - a ], then t… - Vidyadip

MCQ

If $A = [a\,\,b],B = [ - b - a]$ and $C = \left[ \begin{array}{l}\,\,\,\,a\\ - a\end{array} \right]$, then the correct statement is

A
$A = - B$
B
$A + B = A - B$
✓
$AC = BC$
D
$CA = CB$

✓

Answer

Correct option: C.

$AC = BC$

c
(c) $AC = [a\,\,\,b]\,\,\left[ \begin{array}{l}\,\,\,a\\ - a\end{array} \right] = [{a^2} - ab]$

$BC = [ - b\,\,\, - a]\,\left[ \begin{array}{l}\,\,\,a\\ - a\end{array} \right] = [{a^2} - ab]$

$\therefore$ $AC = BC$.

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