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If (x,y,z) ne (0,0,0) and (hati + hatj +...

If `(x,y,z) ne (0,0,0) and (hati + hatj +3hatk )x + (3 hati - 3 hatj + hatk )y +(-4 hati + 5 hatj ) z` `= a (x hati + y hatj + z hatk ),` then the values of a are

A

0, -2

B

2, 0

C

0, -1

D

1, 0

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To solve the given vector equation, we start with the expression: \[ (\hat{i} + \hat{j} + 3\hat{k})x + (3\hat{i} - 3\hat{j} + \hat{k})y + (-4\hat{i} + 5\hat{j})z = a(x\hat{i} + y\hat{j} + z\hat{k}) \] ### Step 1: Expand the Left-Hand Side We will expand the left-hand side by distributing \(x\), \(y\), and \(z\) with their respective coefficients. \[ = (x\hat{i} + x\hat{j} + 3x\hat{k}) + (3y\hat{i} - 3y\hat{j} + y\hat{k}) + (-4z\hat{i} + 5z\hat{j}) \] ### Step 2: Combine Like Terms Now, we combine the coefficients of \(\hat{i}\), \(\hat{j}\), and \(\hat{k}\): - Coefficient of \(\hat{i}\): \(x + 3y - 4z\) - Coefficient of \(\hat{j}\): \(x - 3y + 5z\) - Coefficient of \(\hat{k}\): \(3x + y\) Thus, we can rewrite the left-hand side as: \[ (x + 3y - 4z)\hat{i} + (x - 3y + 5z)\hat{j} + (3x + y)\hat{k} \] ### Step 3: Set Up the Equation Now, we equate the coefficients from both sides of the equation: \[ (x + 3y - 4z) = a x \] \[ (x - 3y + 5z) = a y \] \[ (3x + y) = a z \] ### Step 4: Rearranging the Equations Rearranging each equation gives us: 1. \(x + 3y - 4z - ax = 0\) \(\Rightarrow (1 - a)x + 3y - 4z = 0\) 2. \(x - 3y + 5z - ay = 0\) \(\Rightarrow x + (-3 + a)y + 5z = 0\) 3. \(3x + y - az = 0\) \(\Rightarrow 3x + y - az = 0\) ### Step 5: Form the Determinant We can set up a determinant with the coefficients of \(x\), \(y\), and \(z\): \[ \begin{vmatrix} 1 - a & 3 & -4 \\ 1 & -3 + a & 5 \\ 3 & 1 & -a \end{vmatrix} = 0 \] ### Step 6: Calculate the Determinant Calculating the determinant: \[ = (1 - a)\left((-3 + a)(-a) - 5\right) - 3\left(1(-a) - 5(3)\right) - 4\left(1(1) - 3(-3 + a)\right) \] Expanding this determinant will lead to a cubic equation in \(a\). ### Step 7: Solve the Cubic Equation After simplifying, we find: \[ -a^3 - 2a^2 - a = 0 \] Factoring out \(-a\): \[ -a(a^2 + 2a + 1) = 0 \] This gives us: \[ a = 0 \quad \text{or} \quad a^2 + 2a + 1 = 0 \] The quadratic can be factored as: \[ (a + 1)^2 = 0 \Rightarrow a = -1 \] ### Final Values of \(a\) Thus, the values of \(a\) are: \[ a = 0 \quad \text{and} \quad a = -1 \]

To solve the given vector equation, we start with the expression: \[ (\hat{i} + \hat{j} + 3\hat{k})x + (3\hat{i} - 3\hat{j} + \hat{k})y + (-4\hat{i} + 5\hat{j})z = a(x\hat{i} + y\hat{j} + z\hat{k}) \] ### Step 1: Expand the Left-Hand Side We will expand the left-hand side by distributing \(x\), \(y\), and \(z\) with their respective coefficients. ...
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OBJECTIVE RD SHARMA ENGLISH-ALGEBRA OF VECTORS-Chapter Test
  1. If (x,y,z) ne (0,0,0) and (hati + hatj +3hatk )x + (3 hati - 3 hatj + ...

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  2. If the vectors vec a =2hati + 3hatj +6hatk and vec b are collinear and...

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  3. If vec a , vec b , vec c are three non-zero vectors (no two of which ...

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  4. Vectors vec aa n d vec b are non-collinear. Find for what value of ...

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  5. If the diagonals of a parallelogram are 3 hati + hatj -2hatk and hati ...

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  6. If ABCD is a quadrilateral, then vec(BA) + vec(BC)+vec(CD) + vec(DA)=

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  7. The points with position vectors 60hati+3hatj,40hati-8hatj, ahati-52ha...

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  8. If ABCDEF is a regualr hexagon, then vec(AC) + vec(AD) + vec(EA) + ve...

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  9. In a regular hexagon ABCDEF, vec(AB)+vec(AC)+vec(AD)+vec(AE)+vec(AF)=k...

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  10. If P, Q , R are the mid-points of the sides AB, BC and CA of Delta AB...

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  11. If G is the centroid of the DeltaABC and if G' is the centroid of anot...

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  12. In a quadrilateral ABCD, vec(AB) + vec(DC) =

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  13. If ABCDE is a pentagon, then vec(AB) + vec(AE) + vec(BC) + vec(DC) +...

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  14. If ABCD is a parallelogram, then vec(AC) - vec(BD) =

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  15. In a Delta ABC, " if " vec(AB) = hati - 7hatj + hatk and vec(BC) = 3 ...

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  16. If vectors vec(AB) = -3hati+ 4hatk and vec(AC) = 5hati -2hatj+4hatk ar...

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  17. The position vectors of P and Q are respectively vec a and vec b . If ...

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  18. If the points whose position vectors are 2hati + hatj + hatk , 6hati -...

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  19. The ratio in which hati + 2 hatj + 3 hatk divides the join of -2hati ...

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  20. If OACB is a parallelogrma with vec( OC) = vec(a) and vec( AB) = vec(...

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  21. The position vectors of the points A, B, C are 2 hati + hatj - hatk , ...

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