Analysis of $e^{ix}$ by Maclaurin Formula

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The discussion focuses on analyzing the expression $e^{ix}$ using the Maclaurin formula. It suggests substituting 'ix' into the known formula for $e^x$ to derive the result. Alternatively, it mentions using the power series for cosine and sine, multiplying the sine series by 'i', and then combining it with the cosine series. Both methods yield the same outcome, with the substitution method being quicker. The analysis ultimately leads to the conclusion that $e^{ix} = \cos x + i \sin x$.
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Analyze by Maclaurin formula:
$e^{ix}$
 
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Do you know the 'formula' for ex? If so, try substituting ix for x.
 
You could also do it by looking at the power series of cosx and sinx, and then multiply the sine power series by i and then add the power series of cos on to it, so you get cosx + isinx. Either way will get you the same answer, and the first method would probably be a little quicker.
 
I picked up this problem from the Schaum's series book titled "College Mathematics" by Ayres/Schmidt. It is a solved problem in the book. But what surprised me was that the solution to this problem was given in one line without any explanation. I could, therefore, not understand how the given one-line solution was reached. The one-line solution in the book says: The equation is ##x \cos{\omega} +y \sin{\omega} - 5 = 0##, ##\omega## being the parameter. From my side, the only thing I could...

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