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Let , and . If is a unit vector such that , then is equal…
MATHEMATICS · Single correct · CBSE · Mathematics · Vector Algebra · Vector Algebra
Problem Let a ⃗ = i ^ − j ^ \vec{a} = \hat{i} - \hat{j} a = i ^ − j ^ , b ⃗ = j ^ − k ^ \vec{b} = \hat{j} - \hat{k} b = j ^ − k ^ and c ⃗ = k ^ − i ^ \vec{c} = \hat{k} - \hat{i} c = k ^ − i ^ . If d ⃗ \vec{d} d is a unit vector such that a ⃗ ⋅ d ⃗ = 0 = ( b ⃗ × c ⃗ ) ⋅ d ⃗ \vec{a} \cdot \vec{d} = 0 = (\vec{b} \times \vec{c}) \cdot \vec{d} a ⋅ d = 0 = ( b × c ) ⋅ d , then d ⃗ \vec{d} d is equal to
(1) ± ( i ^ + j ^ − 2 k ^ ) 6 \pm \frac{(\hat{i} + \hat{j} - 2\hat{k})}{\sqrt{6}} ± 6 ( i ^ + j ^ − 2 k ^ )
(2) ± ( i ^ + j ^ − k ^ ) 3 \pm \frac{(\hat{i} + \hat{j} - \hat{k})}{\sqrt{3}} ± 3 ( i ^ + j ^ − k ^ )
(3) ± ( i ^ + j ^ + k ^ ) 3 \pm \frac{(\hat{i} + \hat{j} + \hat{k})}{\sqrt{3}} ± 3 ( i ^ + j ^ + k ^ )
(4) ± k ^ \pm \hat{k} ± k ^
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