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        <title>Question 5, Exercise 2.6</title>
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        <description>Question 5, Exercise 2.6

Solutions of Question 5 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $x_{1}+x_{2}+2 x_{3}=8$$-x_{1}-2 x_{2}+3 x_{3}=1$$3 x_{1}-7 x_{2}+4 x_{3}=10$$A X=B$\begin{align*}
&amp;A = \begin{bmatrix}
1 &amp; 1 &amp; 2 \\
-1 &amp; -2 &amp; 3 \\
3 &amp; -7 &amp; 4
\end{bmatrix}, \quad
X = \begin{bmatrix}
x_1 \\
x_2 \\
x_3
\end{bmatrix}, \quad
B = \…</description>
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        <title>Question 2, Exercise 2.6</title>
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        <description>Question 2, Exercise 2.6

Solutions of Question 2 of Exercise 2.6 of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $\lambda$$\lambda$$2 x_{1}-\lambda x_{2}+x_{3}=0$$2 x_{1}+3 x_{2}-x_{3}=0$$3 x_{1}-2 x_{2}+4 x_{3}=0$\begin{align*}
&amp;2 x_{1}-\lambda x_{2}+x_{3}=0 \cdots(i)\\
&amp;2 x_{1}+3 x_{2}-x_{3}=0\cdots(ii)\\
&amp;3 x_{1}-2 x_{2}+4 x_{3}=0\cdots(iii)\\
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        <title>Question 1, Review Exercise</title>
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        <description>Question 1, Review Exercise

Solutions of Question 1 of Review Exercise of Unit 02: Matrices and Determinants. This is unit of Model Textbook of Mathematics for Class XI published by National Book Foundation (NBF) as Federal Textbook Board, Islamabad, Pakistan. $A$$m \times n$$B$$n \times p$$A B$$n \times p$$m \times p$$p \times m$$n \times n$$A$$1 \times n$$A^{t} A$$1 \times n$$n \times 1$$1 \times 1$$n \times n$$a_{i j}$$A$$a_{i j}=(-1)^{i+j} A_{i j}$$a_{i j}=(-1)^{i+j} M_{i j}$$\frac{A_{i j}}…</description>
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