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Consider the System of Equations: A1x + B1y + C1z = 0 A2x + B2y + C2z = 0 A3x + B3y + C3z = 0,

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Question

Consider the system of equations:
a1x + b1y + c1z = 0
a2x + b2y + c2z = 0
a3x + b3y + c3z = 0,
if \[\begin{vmatrix}a_1 & b_1 & c_1 \\ a_2 & b_2 & c_2 \\ a_3 & b_3 & c_3\end{vmatrix}\]= 0, then the system has

Options

  • more than two solutions

  • one trivial and one non-trivial solutions

  • no solution

  • only trivial solution (0, 0, 0)

MCQ
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Solution

(a) more than two solutions
Here, 
\[\left| A \right| = 0\text{ and }B = 0 \left(\text{ Given }\right)\]
\[\text{ If }\left| A \right|=0\text{ and }\left( adjA \right)B=0,\text{ then the system is consistent and has infinitely many solutions.}\]
Clearly, it has more than two solutions.

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Chapter 7: Solution of Simultaneous Linear Equations - Exercise 8.4 [Page 22]

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R.D. Sharma Mathematics Volume 1 and 2 [English] Class 12
Chapter 7 Solution of Simultaneous Linear Equations
Exercise 8.4 | Q 6 | Page 22

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