Determinants - Solved Examples – Triangle Area Using Determinants

12th Boards Maths Lecture

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<h2 id="solved-example-8-contd">Solved Example 8 (contd.)</h2>
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<li>Expanding along the first row, we get ( \text{Area} = \frac{1}{2} (2 \times 1 + 3 \times (-2) + 1 \times 6) - (1 \times 1 + 1 \times (-2) + (-5) \times 6) )</li>
<li>Simplifying this, we obtain ( \text{Area} = \frac{1}{2} (2 - 6 + 6) - (1 - 2</li>
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