<PRE><B>Question 1207569</B>
&lt;br&gt;
{{{(-8i)^(1/3)}}}&lt;br&gt;
Write the given complex number in cis(theta) form:&lt;br&gt;
{{{(8cis(270))^(1/3)}}}&lt;br&gt;
Use deMoivre&#39;s Theorem to find the principal root:&lt;br&gt;
{{{((8^(1/3))(cis(270/3)))=2cis(90)}}}&lt;br&gt;
Convert the result back to a+bi form:&lt;br&gt;
{{{2(0+i)=2i}}}&lt;br&gt;
ANSWER: 2i&lt;br&gt;
CHECK:
{{{(2i)^3=8i^3=8(-i)=-8i}}}&lt;br&gt;
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