Question

Please find the square roots of the following complex number.

Answer 1

Hey there,

First, find the square root of the given equation.

$\sqrt{z}=\sqrt{81(\text{cos}(\frac{4\pi}{9})+i\text{sin}(\frac{4\pi}{9})}\\=9\text{cos}\frac{1}{2}(2k\pi+(\frac{4\pi}{9}))+i\text{sin}\frac{1}{2} (2k\pi+(\frac{4\pi}{9}))$

Keep in mind that this is solved for k = 0 and 1.

Second, simplify.

$=9\text{cos}(\frac{2\pi}{9})+i\text{sin}(\frac{2\pi}{9})~\text{or}~9\text{cos}(\frac{11\pi}{9})+i\text{sin}(\frac{11\pi}{9})$

Best of Luck!