Class 12 Determinants · Short Answer2 Marksdeterminant_evaluation
Class 12 Maths · Determinants · Short Answer #46
Evaluate \(\begin{vmatrix}x²−x+1 & x−1\\x+1 & x+1\end{vmatrix}\).
✅ Step-by-Step Solution
Final Answer: x³−x²+2
- Apply ad−bc to the 2×2 determinant.
- It equals (x²−x+1)(x+1)−(x−1)(x+1)=(x³+1)−(x²−1).
- Hence the value is x³−x²+2.
📋 CBSE Stepwise Marking Scheme
- [0.5 marks] Apply ad−bc to the 2×2 determinant.
- [1 mark] It equals (x²−x+1)(x+1)−(x−1)(x+1)=(x³+1)−(x²−1).
- [0.5 marks] Hence the value is x³−x²+2.
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