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If → a O + → O B = → B O + → O C , Prove that A, B, C Are Collinear Points. - Mathematics

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Question

If \[\overrightarrow{AO} + \overrightarrow{OB} = \overrightarrow{BO} + \overrightarrow{OC} ,\] prove that A, B, C are collinear points.

Sum
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Solution

We have,
\[\overrightarrow{AO} + \overrightarrow{OB} = \overrightarrow{BO} + \overrightarrow{OC} . \]
\[ \Rightarrow \overrightarrow{AO} - \overrightarrow{BO} = \overrightarrow{OC} - \overrightarrow{OB} . \]
\[ \Rightarrow \overrightarrow{OB} - \overrightarrow{OA} = \overrightarrow{OC} - \overrightarrow{OB} . \]
\[ \Rightarrow \overrightarrow{AB} = \overrightarrow{BC} .\]
Hence A, B and C are collinear points.

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Chapter 23: Algebra of Vectors - Exercise 23.7 [Page 61]

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RD Sharma Mathematics [English] Class 12
Chapter 23 Algebra of Vectors
Exercise 23.7 | Q 6 | Page 61

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