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प्रश्न
Find the direction cosines of the vector `hati + 2hatj + 3hatk`.
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उत्तर
Let `veca = hati + 2hatj + 3hatk`
`therefore |veca| = sqrt(1^2 + 2^2 + 3^2) `
`= sqrt(1 + 4 + 9)`
`= sqrt14`
Hence, the direction cosines of `veca` are `(1/sqrt14, 2/sqrt14, 3/sqrt14)`.
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