Answer: (-1-5i)/2.
- A (-1+5i)/2
- B (-1-5i)/2
- C (2+3i)/(1+i)
- D (2-3i)/(1+i)
Correct answer: B. (-1-5i)/2
Explanation: First simplify: (2+3i)(1+i)/((1-i)(1+i)) = (2+2i+3i+3i<sup>2</sup>)/2 = (2+5i-3)/2 = (-1+5i)/2. Conjugate = (-1-5i)/2.
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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