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Let a be a non-zero vector. If x=i^×(a×i^), y=j^×(a×j^)-a and z=k^×(a×k^)-a, then xyz=
MathematicsVector AlgebraTS EAMCETTS EAMCET 2019 (03 May Shift 2)
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The correct answer is: 0

Given, x=i^×(a×i^), y=j^×(a×j^)-a and z=k^×(a×k^)-a

x=i^·i^a-i^·ai^, y=j^·j^a-j^·aj^-a and z=k^·k^a-k^·ak^-a

x=a-i^·ai^, y=-j^·aj^ and z=-k^.ak^

Let, a=αi^+βj^+γk^, then x=βj^+γk^, y=-βj^ and z=-γk^.

Now, xyz=x·y×z

xyz=βj^+γk^·-βj^×-γk^

xyz=βj^+γk^·βγi^=0

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