Evaluate the following determinant: \[\begin{vmatrix}x & - 7 \\ x & 5x + 1\end{vmatrix}\]

Evaluate the Following Determinant: ∣ ∣ ∣ X − 7 X 5 X + 1 ∣ ∣ ∣ - Mathematics

Question

Evaluate the following determinant:

$| \begin{matrix} x & - 7 \\ x & 5 x + 1 \end{matrix} |$

Solution

$∆ = x (5 x + 1) + 7 x = 5 x^{2} + x + 7 x$
$= 5 x^{2} + 8 x$

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Applications of Determinants and Matrices

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Q 2.1 Q 1.7 Q 2.2

Chapter 6: Determinants - Exercise 6.1 [Page 10]

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RD Sharma Mathematics [English] Class 12

Chapter 6 Determinants
Exercise 6.1 | Q 2.1 | Page 10

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Evaluate the Following Determinant: ∣ ∣ ∣ X − 7 X 5 X + 1 ∣ ∣ ∣ - Mathematics

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