Need to find all z such that z^4 = 16i. Rectangular form and no trig functions. Here's what I did:(adsbygoogle = window.adsbygoogle || []).push({});

z^4 = 16e^(i pi/2) = 16e^i(pi/2 + 2npi)

z = 2e^i(pi/8 + npi/2)

First question: Do I add a 2npi before I take the 4th root or do I add it after I take the 4th root to get z = 2e^i(pi/8 + 2npi)? Does it matter?

Second question: After I get an expression for z, which n's do I plug in the equation to find the 4 z's I'm looking for? How do I know that?

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# Homework Help: Z^4 = 16i

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