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If aa→ and bb→ are the position vectors of A and B, respectively, find the position vector of a point C in BA produced such that BC = 1.5 BA.

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प्रश्न

If `vec"a"` and `vec"b"` are the position vectors of A and B, respectively, find the position vector of a point C in BA produced such that BC = 1.5 BA.

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उत्तर


Given that BC = 1.5 BA

⇒ `"BC"/"BA"` = 1.5 = `3/2`

⇒ `(vec"c" - vec"b")/(vec"a" - vec"b") = 3/2`

⇒ `2vec"c" - 2vec"b" = 3vec"a" - 3vec"b"`

⇒ `2vec"c" = 3vec"a" - 3vec"b" + 2vec"b"`

⇒ `2vec"c" = 3vec"a" - vec"b"`

∴ `vec"c" = (3vec"a" - vec"b")/2`

Hence, the required vector is `vec"c" = (3vec"a" - vec"b")/2`.

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अध्याय 10: Vector Algebra - Exercise [पृष्ठ २१५]

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एनसीईआरटी एक्झांप्लर Mathematics Exemplar [English] Class 12
अध्याय 10 Vector Algebra
Exercise | Q 4 | पृष्ठ २१५

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