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Let a, b and c be real numbers such that...

Let a, b and c be real numbers such that `4a + 2b + c = 0` and `ab gt 0.` Then the equation ax^(2) + bx + c = 0` has

A

complex roots

B

exactly one root

C

real roots

D

none of these

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To solve the problem step by step, we start with the given equations and conditions. ### Step 1: Understand the Given Information We are given: 1. The equation \(4a + 2b + c = 0\). 2. The condition \(ab > 0\). 3. The quadratic equation \(ax^2 + bx + c = 0\). ### Step 2: Substitute Values into the Quadratic Equation We need to analyze the quadratic equation \(ax^2 + bx + c = 0\). We can substitute \(x = 2\) into the equation: \[ a(2^2) + b(2) + c = 0 \] This simplifies to: \[ 4a + 2b + c = 0 \] ### Step 3: Use the Given Condition Since we know from the problem statement that \(4a + 2b + c = 0\), we can conclude that \(x = 2\) is a root of the quadratic equation. ### Step 4: Analyze the Nature of the Roots Since \(x = 2\) is a root, we can factor the quadratic equation as follows: \[ a(x - 2)(x - r) = 0 \] where \(r\) is the other root. ### Step 5: Determine the Nature of the Other Root To determine the nature of the roots, we need to consider the condition \(ab > 0\). This condition implies that both \(a\) and \(b\) are either both positive or both negative. 1. If \(a > 0\) and \(b > 0\), then the parabola opens upwards, and since one root is \(2\), the other root \(r\) must also be real and greater than \(2\). 2. If \(a < 0\) and \(b < 0\), then the parabola opens downwards, and since one root is \(2\), the other root \(r\) must also be real and less than \(2\). ### Step 6: Conclusion In both cases, we find that the quadratic equation has two real roots: one root is \(2\) and the other root \(r\) is real as well. Therefore, the equation \(ax^2 + bx + c = 0\) has two real roots. ### Final Answer The equation \(ax^2 + bx + c = 0\) has **real roots**. ---

To solve the problem step by step, we start with the given equations and conditions. ### Step 1: Understand the Given Information We are given: 1. The equation \(4a + 2b + c = 0\). 2. The condition \(ab > 0\). 3. The quadratic equation \(ax^2 + bx + c = 0\). ...
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