Answer: -i.
- A 1
- B i
- C -1
- D -i
Correct answer: D. -i
Explanation: i<sup>3</sup> = i<sup>2</sup> x i = -1 x i = -i.
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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