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Choose the correct answer. Let `veca"and"vecb` be two unit vectors and `theta` be the angle between them.Then`veca+vecb` is a unit vector, if: a)`theta=pi/4` b)`theta=pi/3` c)`theta=pi/2` d)`theta=(2pi)/3`

A

`theta=pi/4`

B

`theta=pi/3`

C

`theta=pi/2`

D

`theta=(2pi)/3`

Text Solution

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The correct Answer is:
D
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