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If vecaxx(vecaxxvecb)=vecbxx(vecbxxvecc)...

If `vecaxx(vecaxxvecb)=vecbxx(vecbxxvecc)` and `veca.vecb!=0`, then `[(veca,vecb,vecc)]=`

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0

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1

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2

D

3

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The correct Answer is:
To solve the problem, we start with the equation given in the question: \[ \vec{a} \times (\vec{a} \times \vec{b}) = \vec{b} \times (\vec{b} \times \vec{c}) \] ### Step 1: Use the vector triple product identity We can use the vector triple product identity, which states that: \[ \vec{x} \times (\vec{y} \times \vec{z}) = (\vec{x} \cdot \vec{z}) \vec{y} - (\vec{x} \cdot \vec{y}) \vec{z} \] Applying this identity to both sides of the equation: \[ \vec{a} \times (\vec{a} \times \vec{b}) = (\vec{a} \cdot \vec{b}) \vec{a} - (\vec{a} \cdot \vec{a}) \vec{b} \] \[ \vec{b} \times (\vec{b} \times \vec{c}) = (\vec{b} \cdot \vec{c}) \vec{b} - (\vec{b} \cdot \vec{b}) \vec{c} \] ### Step 2: Set the results equal Now we set the two results equal to each other: \[ (\vec{a} \cdot \vec{b}) \vec{a} - (\vec{a} \cdot \vec{a}) \vec{b} = (\vec{b} \cdot \vec{c}) \vec{b} - (\vec{b} \cdot \vec{b}) \vec{c} \] ### Step 3: Rearranging the equation Rearranging gives us: \[ (\vec{a} \cdot \vec{b}) \vec{a} - (\vec{b} \cdot \vec{c}) \vec{b} = (\vec{a} \cdot \vec{a}) \vec{b} - (\vec{b} \cdot \vec{b}) \vec{c} \] ### Step 4: Grouping terms We can group terms involving \(\vec{b}\) and \(\vec{c}\): \[ (\vec{a} \cdot \vec{b}) \vec{a} + (\vec{b} \cdot \vec{b}) \vec{c} = (\vec{a} \cdot \vec{a}) \vec{b} + (\vec{b} \cdot \vec{c}) \vec{b} \] ### Step 5: Dot product with \(\vec{b}\) and \(\vec{c}\) Now we take the dot product of both sides with \(\vec{b} \times \vec{c}\): \[ \left[(\vec{a} \cdot \vec{b}) \vec{a} + (\vec{b} \cdot \vec{b}) \vec{c}\right] \cdot (\vec{b} \times \vec{c}) = \left[(\vec{a} \cdot \vec{a}) \vec{b} + (\vec{b} \cdot \vec{c}) \vec{b}\right] \cdot (\vec{b} \times \vec{c}) \] ### Step 6: Simplifying the dot products Using the property that \(\vec{x} \cdot (\vec{y} \times \vec{z}) = 0\) if \(\vec{x}\) is in the plane formed by \(\vec{y}\) and \(\vec{z}\): The left side simplifies to zero since \(\vec{b} \times \vec{c}\) is perpendicular to both \(\vec{b}\) and \(\vec{c}\). ### Step 7: Conclusion Since \(\vec{a} \cdot \vec{b} \neq 0\) (as given), it implies that the scalar triple product \([\vec{a}, \vec{b}, \vec{c}] = 0\). Thus, we conclude: \[ [\vec{a}, \vec{b}, \vec{c}] = 0 \]

To solve the problem, we start with the equation given in the question: \[ \vec{a} \times (\vec{a} \times \vec{b}) = \vec{b} \times (\vec{b} \times \vec{c}) \] ### Step 1: Use the vector triple product identity We can use the vector triple product identity, which states that: ...
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OBJECTIVE RD SHARMA ENGLISH-SCALAR AND VECTOR PRODUCTS OF THREE VECTORS -Exercise
  1. When a right handed rectangular Cartesian system OXYZ is rotated about...

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  2. Prove that vectors vecu=(al+a(1)l(1))hati+(am+a(1)m(1))hatj + (an+a(...

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  3. If vecaxx(vecaxxvecb)=vecbxx(vecbxxvecc) and veca.vecb!=0, then [(veca...

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  4. [(veca,vecb,axxvecb)]+(veca.vecb)^(2)=

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  5. Let vec(alpha),vec(beta) and vec(gamma be the unit vectors such that v...

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  6. If veca, vecb and vecc are unit coplanar vectors, then [(2veca-3vecb,...

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  7. If [(veca,vecb,vecc)]=3, then the volume (in cubic units) of the paral...

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  8. If V is the volume of the parallelepiped having three coterminous edge...

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  9. Unit vectors veca and vecb ar perpendicular , and unit vector vecc is ...

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  10. If vectors vec A B=-3 hat i+4 hat ka n d vec A C=5 hat i-2 hat j+4 ha...

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  11. Let the position vectors of vertices A,B,C of DeltaABC be respectively...

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  12. The position vector of a point P is vecr=xhati+yhatj+zhatk where x,y,z...

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  13. veca and vecb are two unit vectors that are mutually perpendicular. A...

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  14. If the vectors 2ahati+bhatj+chatk, bhati+chatj+2ahatk and chati+2ahatj...

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  15. Let alpha = a hati + b hatj + chatk , vecbeta = bhati + chatj + ahatk ...

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  16. Let veca,vecb,vecc be three mutually perpendicular vectors having same...

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  17. Let veca,vecb and vecc be the three non-coplanar vectors and vecd be a...

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  18. Let vecr be a unit vector satisfying vecr xx veca = vecb, " where " |v...

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  19. Let veca and vecc be unit vectors such that |vecb|=4 and vecaxxvecb=2(...

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  20. If veca+2vecb+3vecc=0, then vecaxxvecb+vecbxxvecc+veccxxveca=

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