Answer: 3π/4.
- A π/4
- B 3π/4
- C -π/4
- D -3π/4
Correct answer: B. 3π/4
Explanation: z = -1+i is in second quadrant. tan(ref angle) = 1/1 = 1, ref angle = pi/4. arg = pi - pi/4 = 3pi/4.
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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