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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, we need to analyze the given conditions and the quadratic equation \( ax^2 + bx + c = 0 \). ### Step 1: Understand the given conditions We have two conditions: 1. \( 4a + 2b + c = 0 \) 2. \( ab > 0 \) From the second condition, \( ab > 0 \), we can infer that both \( a \) and \( b \) must either be positive or both must be negative. This means that \( a \) and \( b \) cannot be zero. ### Step 2: Substitute the values into the quadratic equation The quadratic equation is given as: \[ ax^2 + bx + c = 0 \] We need to check the nature of the roots of this equation. ### Step 3: Calculate \( f(2) \) We can evaluate the quadratic function at \( x = 2 \): \[ f(2) = a(2^2) + b(2) + c = 4a + 2b + c \] From the first condition, we know that: \[ 4a + 2b + c = 0 \] Thus, we have: \[ f(2) = 0 \] This shows that \( x = 2 \) is a root of the equation \( ax^2 + bx + c = 0 \). ### Step 4: Determine the nature of the roots Since we have found that \( x = 2 \) is a root, we can conclude that the quadratic equation has at least one real root. ### Step 5: Analyze the implications of \( ab > 0 \) Given that \( ab > 0 \), we know that both \( a \) and \( b \) are either positive or negative. This means the parabola opens upwards if \( a > 0 \) or downwards if \( a < 0 \). ### Step 6: Conclusion Since we have established that the quadratic has a real root (specifically \( x = 2 \)), we can conclude that the equation \( ax^2 + bx + c = 0 \) has real roots. Thus, the answer is that the equation has real roots. ### Final Answer The equation \( ax^2 + bx + c = 0 \) has real roots. ---

To solve the problem, we need to analyze the given conditions and the quadratic equation \( ax^2 + bx + c = 0 \). ### Step 1: Understand the given conditions We have two conditions: 1. \( 4a + 2b + c = 0 \) 2. \( ab > 0 \) From the second condition, \( ab > 0 \), we can infer that both \( a \) and \( b \) must either be positive or both must be negative. This means that \( a \) and \( b \) cannot be zero. ...
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