What is the nature of roots of ax^2 + bx + c = 0 if discriminant D = b^2 - 4ac < 0?
Answer and explanation
Correct answer: D. Complex conjugate roots
- Step 1: The roots are given by (-b +- sqrt(D)) / (2a). Step 2. When D < 0, sqrt(D) is imaginary, resulting in two complex conjugate roots. Answer: Complex conjugate roots. Why not the others: Real rational equal occurs when D = 0; real rational unequal occurs when D is a positive perfect square; real irrational occurs when D > 0 is not a perfect square.
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