Category:Arbitrary Power of Complex Number

From ProofWiki
Jump to navigation Jump to search

This category contains pages concerning Arbitrary Power of Complex Number:


Let $z = a + i b$ be a complex number.

Let $n \in \Z_{>0}$ be a (strictly) positive integer.

Then:

\(\ds z^n\) \(=\) \(\ds \paren {\sum_{\substack {0 \mathop \le j \mathop \le n \\ \text {$j$ even} } } \paren {-1}^{j / 2} \dbinom n j a^{n - j} b^j} + i \paren {\sum_{\substack {0 \mathop \le j \mathop \le n \\ \text {$j$ odd} } } \paren {-1}^{\paren {j - 1} / 2} \dbinom n j a^{n - j} b^j}\)
\(\ds \) \(=\) \(\ds \paren {a^n - \dbinom n 2 a^{n - 2} b^2 + \dbinom n 4 a^{n - 4} b^4 - \cdots}\)
\(\ds \) \(\) \(\, \ds + \, \) \(\ds i \paren {\dbinom n 1 a^{n - 1} b - \dbinom n 3 a^{n - 3} b^3 + \cdots}\)

Pages in category "Arbitrary Power of Complex Number"

The following 2 pages are in this category, out of 2 total.