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

If `vecaxx(vecbxxvecc)=vecbxx(veccxxveca)` and `[(vec, vecb, vecc)]!=0`
then `vecaxx(vecbxxvecc)` is equal to

A

`vec0`

B

`vecaxxvecb`

C

`vecbxxvecc`

D

`veccxxveca`

Text Solution

AI Generated Solution

The correct Answer is:
To solve the problem, we start with the given equation: \[ \vec{a} \times (\vec{b} \times \vec{c}) = \vec{b} \times (\vec{c} \times \vec{a}) \] We need to simplify the left-hand side and the right-hand side using the vector triple product identity. ### Step 1: Use the Vector Triple Product Identity The vector triple product identity states that: \[ \vec{a} \times (\vec{b} \times \vec{c}) = (\vec{a} \cdot \vec{c}) \vec{b} - (\vec{a} \cdot \vec{b}) \vec{c} \] Applying this to the left-hand side: \[ \vec{a} \times (\vec{b} \times \vec{c}) = (\vec{a} \cdot \vec{c}) \vec{b} - (\vec{a} \cdot \vec{b}) \vec{c} \] ### Step 2: Simplify the Right-Hand Side Now, we apply the vector triple product identity to the right-hand side: \[ \vec{b} \times (\vec{c} \times \vec{a}) = (\vec{b} \cdot \vec{a}) \vec{c} - (\vec{b} \cdot \vec{c}) \vec{a} \] ### Step 3: Set the Two Sides Equal Now we equate the two results from Step 1 and Step 2: \[ (\vec{a} \cdot \vec{c}) \vec{b} - (\vec{a} \cdot \vec{b}) \vec{c} = (\vec{b} \cdot \vec{a}) \vec{c} - (\vec{b} \cdot \vec{c}) \vec{a} \] ### Step 4: Rearranging the Equation Rearranging gives us: \[ (\vec{a} \cdot \vec{c}) \vec{b} + (\vec{b} \cdot \vec{c}) \vec{a} = (\vec{b} \cdot \vec{a}) \vec{c} + (\vec{a} \cdot \vec{b}) \vec{c} \] ### Step 5: Factor Out Common Terms We can factor out common terms: \[ (\vec{a} \cdot \vec{c}) \vec{b} + (\vec{b} \cdot \vec{c}) \vec{a} = 2(\vec{a} \cdot \vec{b}) \vec{c} \] ### Conclusion Thus, we have shown that: \[ \vec{a} \times (\vec{b} \times \vec{c}) = \vec{b} \times (\vec{c} \times \vec{a}) \implies \vec{a} \times (\vec{b} \times \vec{c}) = (\vec{a} \cdot \vec{c}) \vec{b} - (\vec{a} \cdot \vec{b}) \vec{c} \] Therefore, the expression \(\vec{a} \times (\vec{b} \times \vec{c})\) is equal to: \[ (\vec{a} \cdot \vec{c}) \vec{b} - (\vec{a} \cdot \vec{b}) \vec{c} \]

To solve the problem, we start with the given equation: \[ \vec{a} \times (\vec{b} \times \vec{c}) = \vec{b} \times (\vec{c} \times \vec{a}) \] We need to simplify the left-hand side and the right-hand side using the vector triple product identity. ...
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OBJECTIVE RD SHARMA-SCALAR AND VECTOR PRODUCTS OF THREE VECTORS -Exercise
  1. If vecaxx(vecbxxvecc)=vecbxx(veccxxveca) and [(vec, vecb, vecc)]!=0 ...

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  2. For non zero vectors veca,vecb, vecc |(vecaxxvecb).vec|=|veca||vecb|...

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  3. Let veca=hati+hatj-hatk, vecb=hati-hatj+hatk and vecc be a unit vector...

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  4. If veca lies in the plane of vectors vecb and vecc, then which of the ...

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  5. The value of [(veca-vecb, vecb-vecc, vecc-veca)], where |veca|=1, |vec...

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  6. If veca, vecb, vecc are three non-coplanar mutually perpendicular unit...

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  7. If vecr.veca=vecr.vecb=vecr.vecc=0 for some non-zero vectro vecr, then...

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  8. If the vectors vecr(1)=ahati+hatj+hatk, vecr(2)=hati+bhatj+hatk, vecr(...

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  9. If hata, hatb, hatc are three units vectors such that hatb and hatc ar...

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  10. For any three vectors veca, vecb, vecc the vector (vecbxxvecc)xxveca e...

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  11. For any these vectors veca,vecb, vecc the expression (veca-vecb).{(vec...

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  12. For any vectors vecr the value of hatixx(vecrxxhati)+hatjxx(vecrxxha...

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  13. If the vectors veca=hati+ahatj+a^(2)hatk, vecb=hati+bhatj+b^(2)hatk, v...

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  14. Let veca, vecb, vecc be three non-coplanar vectors and vecp,vecq,vecr ...

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  15. If veca, vecb, vecc are non-coplanar vectors, then (veca.(vecbxxvecc))...

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  16. Let veca=a(1)hati+a(2)hatj+a(3)hatk, vecb=b(1)hati+b(2)hatj+b(3)hatk a...

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  17. If the non zero vectors veca and vecb are perpendicular to each other,...

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  18. Prove that: [(vecaxxvecb)xx(vecaxxvecc)].vecd=pveca vecb vecc](veca.ve...

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  19. If (vecaxxvecb)xxvecc=vecaxx(vecbxxvecc) then

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  20. If veca,vecb,vecc and vecp,vecq,vecr are reciprocal system of vectors,...

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  21. vecaxx(vecaxx(vecaxxvecb)) equals

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