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If `alpha` and `beta` are the roots of the quadratic equation `x^(2) + 3x - 4 = 0`, then `alpha^(-1) + beta^(-1) = "_____"`.

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To solve the problem, we need to find the value of \( \alpha^{-1} + \beta^{-1} \) given that \( \alpha \) and \( \beta \) are the roots of the quadratic equation \( x^2 + 3x - 4 = 0 \). ### Step 1: Identify the roots of the quadratic equation The given quadratic equation is: \[ x^2 + 3x - 4 = 0 \] We can factor this equation. We need two numbers that multiply to \(-4\) (the constant term) and add up to \(3\) (the coefficient of \(x\)). The numbers \(4\) and \(-1\) satisfy this condition because: \[ 4 \times (-1) = -4 \quad \text{and} \quad 4 + (-1) = 3 \] Thus, we can factor the equation as: \[ (x + 4)(x - 1) = 0 \] ### Step 2: Find the roots Setting each factor to zero gives us the roots: \[ x + 4 = 0 \quad \Rightarrow \quad x = -4 \] \[ x - 1 = 0 \quad \Rightarrow \quad x = 1 \] So, the roots are: \[ \alpha = -4 \quad \text{and} \quad \beta = 1 \] ### Step 3: Calculate \( \alpha^{-1} + \beta^{-1} \) Now, we need to find: \[ \alpha^{-1} + \beta^{-1} = \frac{1}{\alpha} + \frac{1}{\beta} \] Substituting the values of \( \alpha \) and \( \beta \): \[ \alpha^{-1} + \beta^{-1} = \frac{1}{-4} + \frac{1}{1} \] ### Step 4: Simplify the expression Calculating this gives: \[ \alpha^{-1} + \beta^{-1} = -\frac{1}{4} + 1 \] To add these fractions, we convert \(1\) to a fraction with a denominator of \(4\): \[ 1 = \frac{4}{4} \] Now we can add: \[ -\frac{1}{4} + \frac{4}{4} = \frac{4 - 1}{4} = \frac{3}{4} \] ### Final Answer Thus, the value of \( \alpha^{-1} + \beta^{-1} \) is: \[ \frac{3}{4} \]
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