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Let us define the length of a vector aha...

Let us define the length of a vector `ahati+bhatj+chatk` and `|a|+|b|+|c|`. This definition coincides with the usual definition of length of a vector `ahati+bhatj+chatk` if an only if

A

a=b=c=0

B

any two of a,b and c are zero

C

any one of a,b and c is zero

D

a+b+c=0

Text Solution

Verified by Experts

The correct Answer is:
B
`|a|+|b|+|c|=sqrt(a^(2)+b^(2)+c^(2))`
`hArr 2|ab|+2|bc|+2|ca|=0`
`hArr ab=bc=ca=0 hArr` any two of a,b and c are zero.
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