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Given a=(1)/(√(10))(3î+k̂) and b=(1)/(7)(2î+3ĵ-6k̂), find the value of (2a-b) [(a×b)×(a+2b) ].

1. -3
2. 5
3. 3
4. -5

Correct answer: -5

Solution

The expression involves vector operations where the cross product and dot product are calculated. The correct option is -5 because the resulting vector from the cross product is orthogonal to both vectors involved, and the dot product with the linear combination of vectors yields this specific value.

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