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If the vectors vec a = 2i+3j+6k and vec ...

If the vectors `vec a = 2i+3j+6k` and `vec b` are collinear and `|vec b| = 21`, then `vec b =`

A

`+-(2i+3j+6k)`

B

`+-(2i+3j+6k)`

C

i+j+k

D

`+-21(2i+3j+6k)`

Text Solution

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The correct Answer is:
D
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HIMALAYA PUBLICATION-VECTORS AND THEIR APPLICATIONS-QUESTION BANK
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