Question
Mathematics Question on Vector Algebra
Let p, q and r be three mutually perpendicular vectors of the same magnitude. If a vector x satisfies equation p x {(x - q) x p} + q x {(x - r) x r} + r x {(x - p) x r} = 0, then x is given by
A
1/2 (p + q - 2r)
B
1/2 (p + q + r)
C
1/3 (2p + q - r)
D
1/3 (2p + q - r)
Answer
1/2 (p + q + r)
Explanation
Solution
Correct option (b) 1/2 (p + q + r)
Let p, q and r be three mutually perpendicular vectors of the same magnitude.
If a vector x satisfies equation p x {(x - q) x p} + q x {(x - r) x r} + r x {(x - p) x r} = 0,
then x is given by