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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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