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student1988
Write the expression in the standard form a + bi. (View my question to see it written, sorry for the inconvenience)
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That's raised to the fourth power.. I got -4. Can someone tell me if i am correct? :)
how did you arrive at your answer?
Is it wrong? i used De Moivre's Theorem
so did you first convert it to the form \(e^{i\theta}\)?
but i wasn't sure if it was right because the complex number i disappeared!
Not sure what you mean by that
your answer is correct - I am just making sure you used this way of getting to the answer rather than trying to expand the braces with the fourth power :)
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the method I used was to first convert it as follows:\[(\sqrt{2}(\cos(3\pi/4)+i\sin(3\pi/4))^4=(\sqrt{2}e^{i3\pi/4})^4\]
oh, i haven't seen this form. Could you tell me where I can read on this form?
it uses the identity:\[e^{i\theta}=\cos(\theta)+i\sin(\theta)\]
Euler's Formula. Thanks, i'll read it! Thank you! :)
Sorry - wrong link, I meant this one: http://en.wikipedia.org/wiki/Euler%27s_formula