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If G and L are the greatest and least va...

If G and L are the greatest and least values of the expression`(2x^(2)-3x+2)/(2x^(2)+3x+2), x epsilonR` respectively. If `L^(2)ltlamdaltG^(2), lamda epsilon N` the sum of all values of `lamda` is

A

1035

B

1081

C

1225

D

1176

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To solve the problem, we need to find the greatest (G) and least (L) values of the expression \( y = \frac{2x^2 - 3x + 2}{2x^2 + 3x + 2} \) and then determine the sum of all natural numbers \( \lambda \) that satisfy \( L^2 < \lambda < G^2 \). ### Step 1: Define the expression Let: \[ y = \frac{2x^2 - 3x + 2}{2x^2 + 3x + 2} \] ### Step 2: Rearrange the equation Multiply both sides by the denominator (assuming it is not zero): \[ y(2x^2 + 3x + 2) = 2x^2 - 3x + 2 \] Rearranging gives: \[ 2x^2y + 3xy + 2y = 2x^2 - 3x + 2 \] This can be rearranged to: \[ (2y - 2)x^2 + (3y + 3)x + (2y - 2) = 0 \] ### Step 3: Apply the discriminant condition For \( x \) to have real solutions, the discriminant \( D \) of the quadratic must be non-negative: \[ D = b^2 - 4ac \geq 0 \] Here, \( a = 2y - 2 \), \( b = 3y + 3 \), and \( c = 2y - 2 \). Thus: \[ D = (3y + 3)^2 - 4(2y - 2)(2y - 2) \geq 0 \] ### Step 4: Simplify the discriminant Calculating \( D \): \[ D = (3y + 3)^2 - 4(2y - 2)^2 \] Expanding: \[ D = 9y^2 + 18y + 9 - 4(4y^2 - 8y + 4) \] \[ = 9y^2 + 18y + 9 - (16y^2 - 32y + 16) \] \[ = -7y^2 + 50y - 7 \geq 0 \] ### Step 5: Solve the quadratic inequality Rearranging gives: \[ 7y^2 - 50y + 7 \leq 0 \] Finding the roots using the quadratic formula: \[ y = \frac{-b \pm \sqrt{b^2 - 4ac}}{2a} = \frac{50 \pm \sqrt{(-50)^2 - 4 \cdot 7 \cdot 7}}{2 \cdot 7} \] Calculating the discriminant: \[ = \sqrt{2500 - 196} = \sqrt{2304} = 48 \] Thus, the roots are: \[ y = \frac{50 \pm 48}{14} \] Calculating the roots: \[ y_1 = \frac{98}{14} = 7, \quad y_2 = \frac{2}{14} = \frac{1}{7} \] ### Step 6: Determine the range of \( y \) The inequality \( 7y^2 - 50y + 7 \leq 0 \) gives the range: \[ \frac{1}{7} \leq y \leq 7 \] Thus, \( L = \frac{1}{7} \) and \( G = 7 \). ### Step 7: Calculate \( L^2 \) and \( G^2 \) Calculating: \[ L^2 = \left(\frac{1}{7}\right)^2 = \frac{1}{49}, \quad G^2 = 7^2 = 49 \] ### Step 8: Find \( \lambda \) values We need to find \( \lambda \) such that: \[ \frac{1}{49} < \lambda < 49 \] The natural numbers satisfying this inequality are \( 1, 2, \ldots, 48 \). ### Step 9: Calculate the sum of \( \lambda \) The sum of the first 48 natural numbers: \[ \text{Sum} = \frac{n(n + 1)}{2} = \frac{48 \cdot 49}{2} = 1176 \] ### Final Answer The sum of all values of \( \lambda \) is: \[ \boxed{1176} \]

To solve the problem, we need to find the greatest (G) and least (L) values of the expression \( y = \frac{2x^2 - 3x + 2}{2x^2 + 3x + 2} \) and then determine the sum of all natural numbers \( \lambda \) that satisfy \( L^2 < \lambda < G^2 \). ### Step 1: Define the expression Let: \[ y = \frac{2x^2 - 3x + 2}{2x^2 + 3x + 2} \] ...
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ARIHANT MATHS ENGLISH-THEORY OF EQUATIONS-Exercise (Passage Based Questions)
  1. If G and L are the greatest and least values of the expression(2x^(2)-...

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  2. If G and L are the greatest and least values of the expression(2x^(2)-...

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  3. If G and L are the greatest and least values of the expression(2x^(2)-...

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  4. If the roots of the equaion x^4-12 x^3+c x^2+dx+81=0 are positive then...

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  5. If the roots of the equaion x^4-12 x^3+c x^2+dx+81=0 are positive then...

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  6. If the roots of the equaion x^4-12 x^3+c x^2+dx+81=0 are positive then...

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  7. In the given figue vertices of DeltaABC lie on y=f(x)=ax^(2)+bx+c. The...

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  8. In the given figue vertices of DeltaABC lie on y=f(x)=ax^(2)+bx+c. The...

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  9. In the given figue vertices of DeltaABC lie on y=f(x)=ax^(2)+bx+c. The...

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  10. Let f(x) = x2 + b1x + c1. g(x) = x^2 + b2x + c2. Real roots of f(x) =...

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  11. Let f(x) = x2 + b1x + c1. g(x) = x^2 + b2x + c2. Real roots of f(x) =...

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  12. Let f(x)=x^(2)+bx+c and g(x)=x^(2)+b(1)x+c(1) Let the real roots of f...

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  13. If ax^2-bx + c=0 have two distinct roots lying in the interval (0,1); ...

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  14. If ax^(2)+bx+c=0 have two distinct roots lying int eh interval (0,1),a...

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  15. If ax^(2)-bx+c=0 have two distinct roots lying in the interval (0,1),a...

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  16. If 2x^(3)+ax^(2)+bx+4=0 (a and b are positive real numbers) has three ...

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  17. If 2x^(3)+ax^(2)+bx+4=0 (a and b are positive real numbers) has three ...

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  18. If 2x^(3)+ax^(2)+bx+4=0 (a and b are positive real numbers) has three ...

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  19. If alpha, beta, gamma are the roots of the equation x^(4)+Ax^(3)+Bx^(2...

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  20. If alpha, beta, gamma, delta are the roots of the equation x^(4)+Ax^(3...

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