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Determinants — MATHS STD 12 Science — Question

Rajasthan BoardEnglish MediumSTD 12 ScienceMATHSDeterminants2 Marks
Question
Evaluate $\left|\begin{array}{cc} {x} & {x+1} \\ {x-1} & {x} \end{array}\right|$
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Answer

We have $\left|\begin{array}{cc} {x} & {x+1} \\ {x-1} & {x} \end{array}\right|$ 
$= x (x) – (x + 1) (x – 1) $
$= x^2 – (x^2 – 1) $
$= x^2 – x^2 + 1 $
$= 1$

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