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If `alpha and beta` are the roots of the equation `x^(2)+alpha x+beta=0` such that `alpha ne beta`, then the number of integral values of x satisfying `||x-beta|-alpha|lt1` is

A

0

B

1

C

2

D

more than 2

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The correct Answer is:
To solve the problem, we need to find the number of integral values of \( x \) that satisfy the inequality \( ||x - \beta| - \alpha| < 1 \), given that \( \alpha \) and \( \beta \) are the roots of the equation \( x^2 + \alpha x + \beta = 0 \) and \( \alpha \neq \beta \). ### Step 1: Understanding the roots From the quadratic equation \( x^2 + \alpha x + \beta = 0 \), we know that: - The sum of the roots \( \alpha + \beta = -\alpha \) (from Vieta's formulas). - The product of the roots \( \alpha \beta = \beta \). From \( \alpha + \beta = -\alpha \), we can rearrange this to get: \[ 2\alpha + \beta = 0 \implies \beta = -2\alpha. \] ### Step 2: Substitute \( \beta \) into the inequality Now, substituting \( \beta = -2\alpha \) into the inequality \( ||x - \beta| - \alpha| < 1 \): \[ ||x + 2\alpha| - \alpha| < 1. \] ### Step 3: Break down the absolute value Let \( y = |x + 2\alpha| - \alpha \). The inequality becomes: \[ |y| < 1. \] This implies: \[ -1 < y < 1. \] Thus, we have: \[ -1 < |x + 2\alpha| - \alpha < 1. \] ### Step 4: Solve the inequalities We can break this into two inequalities: 1. \( |x + 2\alpha| - \alpha < 1 \) 2. \( |x + 2\alpha| - \alpha > -1 \) #### For the first inequality: \[ |x + 2\alpha| < \alpha + 1. \] This means: \[ -\alpha - 1 < x + 2\alpha < \alpha + 1. \] Rearranging gives: \[ -\alpha - 1 - 2\alpha < x < \alpha + 1 - 2\alpha, \] which simplifies to: \[ -3\alpha - 1 < x < -\alpha + 1. \] #### For the second inequality: \[ |x + 2\alpha| > \alpha - 1. \] This means: \[ x + 2\alpha < -(\alpha - 1) \quad \text{or} \quad x + 2\alpha > \alpha - 1. \] Rearranging gives: 1. \( x < -3\alpha + 1 \) 2. \( x > -\alpha - 1 \) ### Step 5: Combine the inequalities Now we combine the results: 1. From the first inequality: \( -3\alpha - 1 < x < -\alpha + 1 \) 2. From the second inequality: \( -3\alpha + 1 > x > -\alpha - 1 \) ### Step 6: Determine the range for \( x \) We need to find the intersection of these ranges: 1. \( -3\alpha - 1 < x < -\alpha + 1 \) 2. \( -3\alpha + 1 > x > -\alpha - 1 \) The combined inequalities give us: \[ -3\alpha - 1 < x < -\alpha + 1 \quad \text{and} \quad -\alpha - 1 < x < -3\alpha + 1. \] ### Step 7: Find integer solutions To find the integer solutions, we need to evaluate the ranges: - The lower bound is \( -3\alpha - 1 \) and the upper bound is \( -\alpha + 1 \). - The lower bound is \( -\alpha - 1 \) and the upper bound is \( -3\alpha + 1 \). We can find the integer values that satisfy both conditions. ### Final Result After evaluating the ranges, we find that the integer values satisfying the inequalities are: - \( -3 \) and \( -1 \). Thus, the number of integral values of \( x \) satisfying the inequality is **2**.
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