If a,b,c Are Position Vectors of the Points A, B, C Respectively Such that 3a+ 5b-8c = 0, Find The Ratio in Which a Divides Bc. - Mathematics and Statistics

प्रश्न

If $\bar{a}, \bar{b}, \bar{c}$ are position vectors of the points A, B, C respectively such that $3 \bar{a} + 5 \bar{b} - 8 \bar{c} = 0$ , find the ratio in which A divides BC.

उत्तर

Given : $3 \bar{a} + 5 \bar{b} - 8 \bar{c} = 0$

$3 \bar{a} = 8 \bar{c} - 5 \bar{b}$

$\bar{a} = \frac{8 \bar{c} - 5 \bar{b}}{3}$

$\bar{a} = \frac{8 \bar{c} - 5 \bar{b}}{8 - 5}$ $[∵ 3 = 8 - 5]$

$A (\bar{a})$ divides BC externally in the ratio 8 : 5.

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Basic Concepts of Vector Algebra

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Q 1.2.5 Q 1.2.4 Q 2.1.1

2016-2017 (July)

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2016-2017 (July) (with solutions)

Q 1.2.5 | 2 marks

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If a,b,c Are Position Vectors of the Points A, B, C Respectively Such that 3a+ 5b-8c = 0, Find The Ratio in Which a Divides Bc. - Mathematics and Statistics

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If a,b,c Are Position Vectors of the Points A, B, C Respectively Such that 3a+ 5b-8c = 0, Find The Ratio in Which a Divides Bc. - Mathematics and Statistics

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