The position vectors of points A, B, C and

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The position vectors of points $A, B, C$ and $D$ are $A = 3\hat i + 4\hat j + 5\hat k,\,\,B = 4\hat i + 5\hat j + 6\hat k,\,\,C = 7\hat i + 9\hat j + 3\hat k$ and $D = 4\hat i + 6\hat j$ then the displacement vectors $AB$ and $CD $ are

A

Perpendicular

B

Antiparallel

C

Parallel

D

Inclined at an angle of $60^°$

The position vectors of points $A, B, C$ and $D$ are $A = 3\hat i + 4\hat j + 5\hat k,\,\,B = 4\hat i + 5\hat j + 6\hat k,\,\,C = 7\hat i + 9\hat j + 3\hat k$ and $D = 4\hat i + 6\hat j$ then the displacement vectors $AB$ and $CD $ are

$\overrightarrow {AB} = (4\hat i + 5\hat j + 6\hat k) - (3\hat i + 4\hat j + 5\hat k)$=$\hat i + \hat j + \hat k$

$\overrightarrow {CD} = (4\hat i + 6\hat j) - (7\hat i + 9\hat j + 3\hat k)$$ = - 3\hat i - 3\hat j - 3\hat k$

$\overrightarrow {AB} $ and $\overrightarrow {CD} $ are anti parallel