Answer: 1 and -1.
- A 0 and 1
- B 1 and -1
- C ±√2
- D None
Correct answer: B. 1 and -1
Explanation: x² = 1 gives x = 1 or x = -1. These are also the factor (x-1)(x+1) = 0.
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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