Mathematics Stack Exchange is a question and answer site for people studying math at any level and professionals in related fields. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

Is it right? \begin{equation}\overline{(-1+i)} = (1-i) \\ \sqrt[4]{-625} = \pm5i \end{equation}
And what does n in this equation means? \begin{equation}z = -\sqrt2 -\sqrt2i \\n= 9\end{equation} Is it some sort of misunderstanding or am I missing something?

share|cite|improve this question
    
Note that $\overline{(-1+i)}$ is actually $-1-i$, not $1-i$. – Stefan Geschke Feb 29 '12 at 21:17
    
There's not enough information in your question to figure out what $n$ means. Could you explain what you're working on? – Jonas Kibelbek Feb 29 '12 at 21:29
up vote 4 down vote accepted

$$ \overline{-1+i} = -1-i $$

The complex conjugate flips the sign of the imaginary part.

To find the nth root of a number, express in polar form first. The rest should be simple. You can easily check your answer by taking your result to the 4th power and seeing if it agrees.

share|cite|improve this answer

Your Answer

 
discard

By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.