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If vec(a)=i-2 j + 3k, vec(b) is a vector...

If `vec(a)=i-2 j + 3k, vec(b)` is a vector such that `vec(a).vec(b)= |vec(b)|^(2) |vec(a)-vec(b)|= sqrt7`, then `|vec(b)|`= ________

A

a.21

B

b.`sqrt7`

C

c.14

D

d.7

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B
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SUNSTAR PUBLICATION-K-CET-MATHEMATICS-2015-MULTIPLE CHOICE QUESTIONS
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