हिंदी

Find the value of 'p' for which the vectors 3i+2j+9k and i-2pj+3k are parallel

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प्रश्न

Find the value of 'p' for which the vectors `3hati+2hatj+9hatk and hati-2phatj+3hatk` are parallel

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उत्तर

We know that for two vectors to be parallel, there direction cosines should have the same ratios.

`∴ 3/1=2/(−2p)=9/3`

`⇒  p=−1/3`

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2013-2014 (March) All India Set 1

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