If ` veca and vecb` are unit vectors inclined to x-axis at angle ` 30^(@) and 120^(@)` then ` |veca +vecb|` equalsA. `sqrt(2//3)`B. `sqrt2`C. `sqrt3`D. 2

If ` veca and vecb` are unit vectors inclined to x-axis at angle ` 30^

1.	If ` veca and vecb` are unit vectors inclined to x-axis at angle ` 30^(@) and 120^(@)` then ` \|veca +vecb\|` equalsA. `sqrt(2//3)`B. `sqrt2`C. `sqrt3`D. 2
Answer» Correct Answer - B Clearly, `veca and vecb` are at angle angle. ` \|veca +vecb\|^(2) =\|vecb\|^(2) +2\|veca\|\|vecb\| cos 90^(@)` ` Rightarrow \| veca +vecb\|^(2) = 1+ 1+0=2 Rightarrow \|veca + vecb\| = sqrt2`

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If ` veca and vecb` are unit vectors inclined to x-axis at angle ` 30^(@) and 120^(@)` then ` |veca +vecb|` equalsA. `sqrt(2//3)`B. `sqrt2`C. `sqrt3`D. 2

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