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If the vectors veca=hati+ahatj+a^(2)hatk...

If the vectors `veca=hati+ahatj+a^(2)hatk, vecb=hati+bhatj+b^(2)hatk, vecc=hati+chatj+c^(2)hatk` are three non-coplanar vectors and `| (a, a^(2), 1+a^(3)),(b,b^(2),1+b^(3)),(c,c^(2),1+c^(3))|=0` , then the value of `abc` is

A

0

B

1

C

2

D

`-1`

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The correct Answer is:
To solve the given problem, we need to analyze the condition provided for the vectors \( \vec{a}, \vec{b}, \vec{c} \) and the determinant condition. Let's break down the solution step by step. ### Step 1: Write down the vectors The vectors are given as: \[ \vec{a} = \hat{i} + a\hat{j} + a^2\hat{k} \] \[ \vec{b} = \hat{i} + b\hat{j} + b^2\hat{k} \] \[ \vec{c} = \hat{i} + c\hat{j} + c^2\hat{k} \] ### Step 2: Formulate the determinant We need to analyze the determinant: \[ \begin{vmatrix} 1 & a & a^2 \\ 1 & b & b^2 \\ 1 & c & c^2 \end{vmatrix} \] This determinant represents the condition for the vectors to be non-coplanar. For non-coplanarity, this determinant must not equal zero. ### Step 3: Calculate the determinant Calculating the determinant, we have: \[ = 1 \cdot (b \cdot b^2 - c \cdot b^2) - a \cdot (1 \cdot b^2 - 1 \cdot c^2) + a^2 \cdot (1 \cdot c - 1 \cdot b) \] This simplifies to: \[ = (b - c)(b^2 - a^2) + (c - b)(a^2 - b^2) + (a - b)(c - a) \] This determinant must not equal zero for the vectors to be non-coplanar. ### Step 4: Analyze the given condition We are also given that: \[ \begin{vmatrix} 1 & a^2 & 1 + a^3 \\ 1 & b^2 & 1 + b^3 \\ 1 & c^2 & 1 + c^3 \end{vmatrix} = 0 \] This determinant equals zero, which implies that the vectors are coplanar in this context. ### Step 5: Simplify the determinant Using row operations, we can simplify the determinant: 1. Subtract the first row from the second and third rows: \[ \begin{vmatrix} 1 & a^2 & 1 + a^3 \\ 0 & b^2 - a^2 & b^3 - a^3 \\ 0 & c^2 - a^2 & c^3 - a^3 \end{vmatrix} \] 2. This leads to: \[ = (b^2 - a^2)(c^3 - a^3) - (c^2 - a^2)(b^3 - a^3) \] 3. Factor out the differences: \[ = (b - a)(b + a)(c - a)(c + a) = 0 \] ### Step 6: Solve for \( abc \) Since the determinant is zero, we can conclude that: \[ 1 + abc = 0 \] Thus, we find: \[ abc = -1 \] ### Final Answer The value of \( abc \) is: \[ \boxed{-1} \]

To solve the given problem, we need to analyze the condition provided for the vectors \( \vec{a}, \vec{b}, \vec{c} \) and the determinant condition. Let's break down the solution step by step. ### Step 1: Write down the vectors The vectors are given as: \[ \vec{a} = \hat{i} + a\hat{j} + a^2\hat{k} \] \[ ...
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OBJECTIVE RD SHARMA-SCALAR AND VECTOR PRODUCTS OF THREE VECTORS -Exercise
  1. For any these vectors veca,vecb, vecc the expression (veca-vecb).{(vec...

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

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

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

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

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

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

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

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

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  11. vecaxx(vecaxx(vecaxxvecb)) equals

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

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  13. If veca, vecb, vecc are non-coplanar unit vectors such that vecaxx(vec...

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  14. Let a,b,c be distinct non-negative numbers. If the vectors ahati+ahatj...

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  15. If vecaxxvecb=vecc and vecbxxvecc=veca then a. veca,vecb,vecc are ort...

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  16. If vecp=(vecbxxvecc)/([(veca,vecb,vecc)]),vecq=(veccxxveca)/([(veca,ve...

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  17. If vecrxxveca=vecbxxveca,vecrxxvecb=vecaxxvecb,veca!=0,vecb!=0,veca!=l...

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  18. The vector veca coplanar with the vectors hati and hatj perendicular t...

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  19. If the vectors veca and vecb are mutually perpendicular, then vecaxx{v...

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  20. [((vecaxxvecb)xx(vecbxxvecc),(vecbxxvecc)xx(veccxxveca),(veccxxveca)xx...

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