# Math Help - Determine the sq root of complex number

1. $z = 3 + 4i = 5\,\textrm{cis}\,\arctan{\frac{4}{3}}$.

2. You have already been told that several times. You appear to have extreme difficulty understanding the responses you get.

3. That because every one iS providing different answers..........mite

freaking me out

4. You have been told repeatedly that the magnitude is r= 5 and that the argument (or amplitude), angle, is $tan^{-1}(3/4)$. The polar form is either $5(cos(tan^{-1}(3/4)+ i sin(tan^{-1}(3/4))$ or $5 e^{itan^{-1}(3/4)}$. Your equation is $z^2= 5 e^{i tan^{-1}(3/4)}$. $z= \sqrt{5}e^{i tan^{-1}(3/4)/2}$.

However, your original question was to find the square roots of 3+ 4i and bigwave, in his first response, showed you how to do that without using the polar form.

5. The angle is actually

$\theta = \arctan{\frac{\mathbf{Im}z}{\mathbf{Re}z}} = \arctan{\frac{4}{3}}$.

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