Mathematics 9709 · AS & A Level · Complex numbers

Complex numbers — practice question

(a)[5]

Find the complex number $z$ that satisfies the equation $z + \frac{iz}{z^*} - 2 = 0$, with $z^*$ as the complex conjugate of $z$. Express your answer in the form $x + iy$, where $x$ and $y$ are real.

(b(i))[2]

On one Argand diagram sketch the loci described by $|z - 2i| = 2$ and $\operatorname{Im} z = 3$, where $\operatorname{Im} z$ means the imaginary part of $z$.

(b(ii))[2]

In the first quadrant, the two loci meet at point $P$. Find the exact argument of the complex number shown by $P$.

Worked solution & mark scheme

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