Derivative using complex exponential

forty
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I'm trying find the 15th derivative of exp[(1 + i(3^.5))theta] with respect to theta

To do this do i need to split it into two exponentials, (e^theta).(e^i(3^.5)theta) ??
 
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What is the derivative of eax with respect to x? What is its second derivative? What is its 15th derivative? Do you see my point?
 
[(1+i(3^.5))^15].e^[(1+i(3^.5))theta]

So i can just apply the normal rules for exponentials ??
 
Yes, 1+i(3^.5) is "just a number". You might want to use De Moivre's formula to caculate (1+ i\sqrt{3})^{15} itself.
 
There are two things I don't understand about this problem. First, when finding the nth root of a number, there should in theory be n solutions. However, the formula produces n+1 roots. Here is how. The first root is simply ##\left(r\right)^{\left(\frac{1}{n}\right)}##. Then you multiply this first root by n additional expressions given by the formula, as you go through k=0,1,...n-1. So you end up with n+1 roots, which cannot be correct. Let me illustrate what I mean. For this...
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