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Question
Write two different vectors having same direction.
Solution
Let `veca = hati + hatj + hatk` and `vecb = 2hati + 2hatj + 2hatk`
Direction cosines of `veca < 1/sqrt3, 1/sqrt3, 1/sqrt3 >`
Direction cosines of
`vecb < 2/sqrt12, 2/sqrt12, 2/sqrt12 >`
Hence `veca ne vecb "but" vec b` have same direction.
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