Answer: -b/a.
- A c/a
- B b/a
- C -b/a
- D -c/a
Correct answer: C. -b/a
Explanation: Sum of roots alpha + beta = -b/a (Vieta's formula).
A complex number z = a+ib is plotted as a point (or vector from the origin) on the Argand plane, with the real part along the horizontal axis and the imaginary part along the vertical; its modulus |z| is the vector's length, and its argument θ is the angle from the positive real axis.
Concept context
Complex numbers in a+ib form, modulus, argument, polar form, cube roots of unity, and quadratic equations with complex roots
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