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If theta is the angle between two vecto...

If `theta` is the angle between two vectors ` veca` and `vecb`, then ` veca*vecb ge 0` only when
(A) `0 lt theta lt pi/2`
(B) `0 le theta le pi/2`
(C) `0 lt theta lt pi`
(D)`0 le theta le pi`

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Verified by Experts

Here is the solution:
`|veca|=+ive!=0`
`|vecb|+ive!=0`
`veca.vecb>=0`
`|veca||vecb| cos theta>=0`
`cos theta>=0`
`0<=theta<=pi/2`
So, B option is correct
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