Answer: 6.
- A 4
- B 6
- C 8
- D 10
Correct answer: B. 6
Explanation: z=1+i, z̄=1-i. Compute zz̄=|z|²=1²+1²=2. Compute z+z̄=(1+i)+(1-i)=2 (imaginary parts cancel). (z+z̄)²=2²=4. Sum: zz̄+(z+z̄)²=2+4=6. Answer: 6
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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