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If alpha and beta are the roots of ax^2...

If `alpha` and `beta` are the roots of `ax^2 + bx + c = 0`, find the equation whose roots are `alpha +2` and `beta +2`.

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To find the equation whose roots are \( \alpha + 2 \) and \( \beta + 2 \), we can follow these steps: ### Step 1: Identify the roots of the original equation The original quadratic equation is given by: \[ ax^2 + bx + c = 0 \] The roots of this equation are \( \alpha \) and \( \beta \). ### Step 2: Use the relationships for the sum and product of the roots From Vieta's formulas, we know: - The sum of the roots \( \alpha + \beta = -\frac{b}{a} \) - The product of the roots \( \alpha \beta = \frac{c}{a} \) ### Step 3: Find the new roots The new roots we are interested in are: \[ \alpha + 2 \quad \text{and} \quad \beta + 2 \] ### Step 4: Calculate the sum of the new roots The sum of the new roots is: \[ (\alpha + 2) + (\beta + 2) = \alpha + \beta + 4 \] Substituting the value of \( \alpha + \beta \): \[ \alpha + \beta + 4 = -\frac{b}{a} + 4 \] ### Step 5: Calculate the product of the new roots The product of the new roots is: \[ (\alpha + 2)(\beta + 2) = \alpha \beta + 2\alpha + 2\beta + 4 \] Substituting the values of \( \alpha + \beta \) and \( \alpha \beta \): \[ \alpha \beta + 2(\alpha + \beta) + 4 = \frac{c}{a} + 2\left(-\frac{b}{a}\right) + 4 \] This simplifies to: \[ \frac{c}{a} - \frac{2b}{a} + 4 = \frac{c - 2b + 4a}{a} \] ### Step 6: Form the new quadratic equation Using the sum and product of the new roots, we can form the new quadratic equation: \[ x^2 - \text{(sum of roots)} \cdot x + \text{(product of roots)} = 0 \] Substituting the values we found: \[ x^2 - \left(-\frac{b}{a} + 4\right)x + \frac{c - 2b + 4a}{a} = 0 \] ### Step 7: Multiply through by \( a \) to eliminate the fraction Multiplying the entire equation by \( a \): \[ ax^2 + \left(b - 4a\right)x + (c - 2b + 4a) = 0 \] ### Final Answer The equation whose roots are \( \alpha + 2 \) and \( \beta + 2 \) is: \[ ax^2 + (b - 4a)x + (c - 2b + 4a) = 0 \]
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