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DETERMINANTS — Maths STD 12 Science — Question

Gujarat BoardEnglish MediumSTD 12 ScienceMathsDETERMINANTS1 Mark
Question
Evaluate $\begin{bmatrix}2&5\\-1&-1\end{bmatrix}$
  1. 3
  2. -7
  3. 5
  4. -2
✓

Answer

  1. 3

Solution:

Expanding along $\text{R}_1,$ we get

$\triangle=2(-1)-5(-1)=2+5$

$=3$

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