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If vec(e(1)) and vec(e(2)) are two unit ...

If `vec(e_(1))` and `vec(e_(2))` are two unit vectors and `theta` is the angle between them, then `sin (theta/2)` is:

A

`1/2 |vec(e)_(1)+vec(e)_(2)|`

B

`1/2 |vec(e)_(1)-vec(e)_(2)|`

C

`(vec(e)_(1).vec(e)_(2))/(2)`

D

`(|vec(e)_(1)xxvec(e)_(2)|)/(2|vec(e)_(1)||vec(e)_(2)|)`

Text Solution

Verified by Experts

The correct Answer is:
B
`|vec(e)_(1)-vec(e)_(2)|=sqrt(1^(2)+1^(2)-2(1)(1) cos theta)=2 "sin" theta/2`
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