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If veca, vecb, vecc are non coplanar vec...

If `veca, vecb, vecc` are non coplanar vectors and `lamda` is a real number, then the vectors `veca+2vecb+3vecc, lamdavecb+4vecc` and `(2lamda-1)vecc` are non coplanar for

A

no value of `lamda`

B

all except one value of `lamda`

C

all except two values of `lamda`

D

all values of `lamda`

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To determine the values of \(\lambda\) for which the vectors \(\vec{a} + 2\vec{b} + 3\vec{c}\), \(\lambda\vec{b} + 4\vec{c}\), and \((2\lambda - 1)\vec{c}\) are non-coplanar, we can use the concept of the determinant of a matrix formed by these vectors. The vectors are non-coplanar if the determinant of the matrix formed by their coefficients is non-zero. ### Step-by-step Solution: 1. **Identify the Vectors**: - Let \(\vec{x} = \vec{a} + 2\vec{b} + 3\vec{c}\) - Let \(\vec{y} = \lambda\vec{b} + 4\vec{c}\) - Let \(\vec{z} = (2\lambda - 1)\vec{c}\) 2. **Set Up the Determinant**: We need to form a matrix with the coefficients of \(\vec{a}\), \(\vec{b}\), and \(\vec{c}\): \[ \begin{vmatrix} 1 & 2 & 3 \\ 0 & \lambda & 4 \\ 0 & 0 & 2\lambda - 1 \end{vmatrix} \] 3. **Calculate the Determinant**: The determinant can be calculated as follows: \[ D = 1 \cdot \begin{vmatrix} \lambda & 4 \\ 0 & 2\lambda - 1 \end{vmatrix} - 2 \cdot \begin{vmatrix} 0 & 4 \\ 0 & 2\lambda - 1 \end{vmatrix} + 3 \cdot \begin{vmatrix} 0 & \lambda \\ 0 & 0 \end{vmatrix} \] The second and third determinants are zero since they have rows of zeros. Thus, we only need to compute the first determinant: \[ D = 1 \cdot (\lambda(2\lambda - 1) - 0) = \lambda(2\lambda - 1) \] 4. **Set the Determinant Not Equal to Zero**: For the vectors to be non-coplanar, we require: \[ \lambda(2\lambda - 1) \neq 0 \] 5. **Solve the Inequality**: This gives us two conditions: - \(\lambda \neq 0\) - \(2\lambda - 1 \neq 0 \Rightarrow \lambda \neq \frac{1}{2}\) 6. **Conclusion**: The vectors \(\vec{a} + 2\vec{b} + 3\vec{c}\), \(\lambda\vec{b} + 4\vec{c}\), and \((2\lambda - 1)\vec{c}\) are non-coplanar for all values of \(\lambda\) except \(\lambda = 0\) and \(\lambda = \frac{1}{2}\).

To determine the values of \(\lambda\) for which the vectors \(\vec{a} + 2\vec{b} + 3\vec{c}\), \(\lambda\vec{b} + 4\vec{c}\), and \((2\lambda - 1)\vec{c}\) are non-coplanar, we can use the concept of the determinant of a matrix formed by these vectors. The vectors are non-coplanar if the determinant of the matrix formed by their coefficients is non-zero. ### Step-by-step Solution: 1. **Identify the Vectors**: - Let \(\vec{x} = \vec{a} + 2\vec{b} + 3\vec{c}\) - Let \(\vec{y} = \lambda\vec{b} + 4\vec{c}\) - Let \(\vec{z} = (2\lambda - 1)\vec{c}\) ...
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OBJECTIVE RD SHARMA ENGLISH-SCALAR AND VECTOR PRODUCTS OF THREE VECTORS -Exercise
  1. If veca, vecb, vecc are non coplanar vectors and lamda is a real numbe...

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  2. For non-zero vectors veca, vecb and vecc , |(veca xx vecb) .vecc| = |v...

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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 mutually perpendicular unit ve...

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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 ahati+hatj+hatk, hati+bhatj+hatk, hati+hatj+chatk(a!=1,...

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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 three vectors, veca, vecb and vecc , (veca-vecb) . (vecb -vecc...

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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 noncolanar vectors and vecp,vecq,vecr are ...

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  15. If vecA, vecB and vecC are three non - coplanar vectors, then (vecA.ve...

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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 an...

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  17. If non-zero vectors veca and vecb are perpendicular to each ot...

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  18. show that (vecaxxvecb)xxvecc=vecaxx(vecbxxvecc) if and only if veca a...

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

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  20. vecaxx(vecaxx(vecaxxvecb)) equals

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  21. If veca =hati + hatj, vecb = hati - hatj + hatk and vecc is a unit vec...

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