मराठी

The Position Vectors of Points A, B and C Are λ ^ I + 3 ^ J ,12 ^ I + μ ^ J and 11 ^ I − 3 ^ J Respectively. If C Divides the Line Segment Joining a and B in the Ratio 3:1, F - Mathematics

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प्रश्न

The position vectors of points A, B and C  are \[\lambda \hat{i} +\] 3 \[\hat{j}\],12\[\hat{i} + \mu\] \[\hat{j}\] and 11\[\hat{i} -\] 3 \[\hat{j}\] respectively. If C divides the line segment joining and B in the ratio 3:1, find the values of \[\lambda\] and \[\mu\]

बेरीज

उत्तर

The position vectors of points A, B and C  are \[\lambda \hat{i} +\] 3 \[\hat{j}\],12\[\hat{i} + \mu\] \[\hat{j}\] and 11\[\hat{i} -\] 3 \[\hat{j}\] respectively.
It is given that, C divides the line segment joining A and B in the ratio 3 : 1.
\[11 \hat{i} - 3 \hat{j} = \frac{3 \times \left( 12 \hat{i} + \mu \hat{j} \right) + 1 \times \left( \lambda \hat{i} + 3 \hat{j} \right)}{3 + 1}\]
\[ \Rightarrow 11 \hat{i} - 3 \hat{j} = \frac{\left( 36 + \lambda \right) \hat{i} + \left( 3\mu + 3 \right) \hat{j} }{4}\]
\[ \Rightarrow 44 \hat{i} - 12 \hat{j} = \left( 36 + \lambda \right) \hat{i} + \left( 3\mu + 3 \right) \hat{j}\]
Equating the corresponding components, we get \[36 + \lambda = 44\]
\[\Rightarrow \lambda = 44 - 36 = 8\]

and

\[\Rightarrow 3\mu + 3 = -12 \]

\[\Rightarrow 3\mu = - 12 - 3 = - 15\]
\[\Rightarrow \mu = - 5\]
Thus, the values of \[\lambda\] and \[\mu\] are 8 and −5, respectively.

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Position Vector of a Point Dividing a Line Segment in a Given Ratio
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पाठ 23: Algebra of Vectors - Exercise 23.4 [पृष्ठ ४३]

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आरडी शर्मा Mathematics [English] Class 12
पाठ 23 Algebra of Vectors
Exercise 23.4 | Q 11 | पृष्ठ ४३

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