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The values of m for which the equation 5...

The values of m for which the equation `5x^(2)-4x+2+m(4x^(2)-2x-1)=0` will have (i) Equal roots (ii) Product of roots as 2 (iii) Sum of the roots as 6 are ……. And ……..

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To solve the given problem, we need to analyze the quadratic equation: \[ 5x^2 - 4x + 2 + m(4x^2 - 2x - 1) = 0 \] We will rewrite this equation in the standard form \( ax^2 + bx + c = 0 \). ### Step 1: Combine Like Terms First, we will combine the coefficients of \( x^2 \), \( x \), and the constant term. - Coefficient of \( x^2 \): \( 5 + 4m \) - Coefficient of \( x \): \( -4 - 2m \) - Constant term: \( 2 - m \) So, the quadratic equation can be rewritten as: \[ (5 + 4m)x^2 + (-4 - 2m)x + (2 - m) = 0 \] ### Step 2: Equal Roots Condition For the quadratic equation to have equal roots, the discriminant must be zero. The discriminant \( D \) is given by: \[ D = b^2 - 4ac \] Substituting \( a = 5 + 4m \), \( b = -4 - 2m \), and \( c = 2 - m \): \[ D = (-4 - 2m)^2 - 4(5 + 4m)(2 - m) \] Expanding this: \[ D = (16 + 16m + 4m^2) - 4[(10 - 5m + 8m - 4m^2)] \] \[ D = 16 + 16m + 4m^2 - 4(10 + 3m - 4m^2) \] \[ D = 16 + 16m + 4m^2 - 40 - 12m + 16m^2 \] Combining like terms: \[ D = 20m^2 + 4m - 24 \] Setting the discriminant equal to zero for equal roots: \[ 20m^2 + 4m - 24 = 0 \] ### Step 3: Solve the Quadratic Equation Dividing through by 4: \[ 5m^2 + m - 6 = 0 \] Now we can factor this: \[ (5m - 6)(m + 1) = 0 \] Setting each factor to zero gives us: \[ m = \frac{6}{5} \quad \text{or} \quad m = -1 \] ### Step 4: Product of Roots Condition For the product of the roots to be 2, we use the formula: \[ \text{Product of roots} = \frac{c}{a} = 2 \] Substituting \( c = 2 - m \) and \( a = 5 + 4m \): \[ \frac{2 - m}{5 + 4m} = 2 \] Cross-multiplying: \[ 2 - m = 2(5 + 4m) \] Expanding: \[ 2 - m = 10 + 8m \] Rearranging gives: \[ 2 - 10 = 9m \quad \Rightarrow \quad -8 = 9m \quad \Rightarrow \quad m = -\frac{8}{9} \] ### Step 5: Sum of Roots Condition For the sum of the roots to be 6, we use the formula: \[ \text{Sum of roots} = -\frac{b}{a} = 6 \] Substituting \( b = -4 - 2m \) and \( a = 5 + 4m \): \[ -\frac{-4 - 2m}{5 + 4m} = 6 \] This simplifies to: \[ \frac{4 + 2m}{5 + 4m} = 6 \] Cross-multiplying: \[ 4 + 2m = 6(5 + 4m) \] Expanding: \[ 4 + 2m = 30 + 24m \] Rearranging gives: \[ 4 - 30 = 22m \quad \Rightarrow \quad -26 = 22m \quad \Rightarrow \quad m = -\frac{13}{11} \] ### Final Answers The values of \( m \) for the three conditions are: 1. Equal roots: \( m = \frac{6}{5} \) or \( m = -1 \) 2. Product of roots = 2: \( m = -\frac{8}{9} \) 3. Sum of roots = 6: \( m = -\frac{13}{11} \)
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