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Let 4x^(2)-4(alpha-2)x + alpha-2=0(alpha...

Let `4x^(2)-4(alpha-2)x + alpha-2=0(alpha in R)` be a quadratic equation. Find the values of `alpha` for which
Both the roots are real and distinct.

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To solve the quadratic equation \( 4x^2 - 4(\alpha - 2)x + (\alpha - 2) = 0 \) for values of \( \alpha \) such that both roots are real and distinct, we need to analyze the discriminant of the equation. ### Step-by-Step Solution: 1. **Identify the coefficients**: The given quadratic equation is in the form \( Ax^2 + Bx + C = 0 \), where: - \( A = 4 \) - \( B = -4(\alpha - 2) \) - \( C = \alpha - 2 \) 2. **Calculate the discriminant**: The discriminant \( D \) of a quadratic equation is given by: \[ D = B^2 - 4AC \] Substituting the values of \( A \), \( B \), and \( C \): \[ D = \left(-4(\alpha - 2)\right)^2 - 4 \cdot 4 \cdot (\alpha - 2) \] 3. **Simplify the discriminant**: Calculate \( D \): \[ D = 16(\alpha - 2)^2 - 16(\alpha - 2) \] Factor out \( 16 \): \[ D = 16\left((\alpha - 2)^2 - (\alpha - 2)\right) \] 4. **Set the discriminant greater than zero**: For the roots to be real and distinct, the discriminant must be greater than zero: \[ 16\left((\alpha - 2)^2 - (\alpha - 2)\right) > 0 \] Dividing both sides by 16 (since 16 is positive): \[ (\alpha - 2)^2 - (\alpha - 2) > 0 \] 5. **Let \( y = \alpha - 2 \)**: Substitute \( y \) into the inequality: \[ y^2 - y > 0 \] Factor the expression: \[ y(y - 1) > 0 \] 6. **Find the critical points**: The critical points are \( y = 0 \) and \( y = 1 \). We will analyze the intervals determined by these points: \( (-\infty, 0) \), \( (0, 1) \), and \( (1, \infty) \). 7. **Test the intervals**: - For \( y < 0 \) (e.g., \( y = -1 \)): \( (-1)(-2) > 0 \) (True) - For \( 0 < y < 1 \) (e.g., \( y = 0.5 \)): \( (0.5)(-0.5) < 0 \) (False) - For \( y > 1 \) (e.g., \( y = 2 \)): \( (2)(1) > 0 \) (True) 8. **Conclusion for \( y \)**: The solution to the inequality \( y(y - 1) > 0 \) is: \[ y < 0 \quad \text{or} \quad y > 1 \] Converting back to \( \alpha \): \[ \alpha - 2 < 0 \quad \Rightarrow \quad \alpha < 2 \] \[ \alpha - 2 > 1 \quad \Rightarrow \quad \alpha > 3 \] 9. **Final answer**: Thus, the values of \( \alpha \) for which both roots are real and distinct are: \[ \alpha \in (-\infty, 2) \cup (3, \infty) \]
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FIITJEE-QUADRATIC EQUATION & EXPRESSION -ASSIGNMENT PROBLEMS (SUBJECTIVE) Level - II
  1. Let 4x^(2)-4(alpha-2)x + alpha-2=0(alpha in R) be a quadratic equation...

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