# Products and quotients of complex numbers

**Products and quotients of complex numbers (Question)**

Given that z_{1} = 3 + i and z_{2} = 2-3i. Determine the following in the form of r(cos x + sin x i).

- z
_{1}z_{2} - z
_{1}/z_{2}

*Guide: *

|z_{1}z_{2}| = r_{1}r_{2}, arg(z_{1}z_{2}) = x_{1} + x_{2}

|z_{1}/z_{2}| = r_{1}/r_{2}, arg(z_{1}/z_{2}) = x_{1} – x_{2}

**Products and quotients of complex numbers (Answer)**

- √130(cos 0.789π + sin 0.789π i)
- √(10/13)(cos -0.585π + sin -0.585π i)

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