Let ` veca , vecb , vecc` be unit vectors such that ` veca .vecb =0=veca.vecc` . If the angle between `vecb and vecc " is " pi/6 , " then " veca ` equalsA. ` +- 2(vecb xx vecc)`B. ` 2(vecb xx vecc)`C. ` +- 1/2(vecb xx vecc)`D. ` - 1/2 (vecb xx vecc)`

Let ` veca , vecb , vecc` be unit vectors such that ` veca .vecb =0=ve

1.	Let ` veca , vecb , vecc` be unit vectors such that ` veca .vecb =0=veca.vecc` . If the angle between `vecb and vecc " is " pi/6 , " then " veca ` equalsA. ` +- 2(vecb xx vecc)`B. ` 2(vecb xx vecc)`C. ` +- 1/2(vecb xx vecc)`D. ` - 1/2 (vecb xx vecc)`
Answer» Correct Answer - A we have , ` veca.vecb= veca.vecc = vec0` ` Rightarrow veca bot vecb, veca bot vecc` ` Rightarrow veca \|\| (vecb xx vecc)` ` Rightarrow veca = +- (vecb xx vecc)/(\|vecb xx vecc\|) =+- (\|vecb xx vecc\|)/(\|vecb\|\|vecc\| sin pi/3) = +- 2 ( vecb xx vecc)`

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Let ` veca , vecb , vecc` be unit vectors such that ` veca .vecb =0=veca.vecc` . If the angle between `vecb and vecc " is " pi/6 , " then " veca ` equalsA. ` +- 2(vecb xx vecc)`B. ` 2(vecb xx vecc)`C. ` +- 1/2(vecb xx vecc)`D. ` - 1/2 (vecb xx vecc)`

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