Answer: -1.
- A -1
- B 0
- C 1
- D 2
Correct answer: A. -1
Explanation: omega<sup>3</sup> = 1. 100 = 33×3 + 1, omega<sup>100</sup> = omega. 200 = 66×3 + 2, omega<sup>200</sup> = omega². omega + omega² = -1 (sum of cube roots of unity).
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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