Lösung 3.4:3
Aus Online Mathematik Brückenkurs 2
(Unterschied zwischen Versionen)
K (Lösning 3.4:3 moved to Solution 3.4:3: Robot: moved page) |
|||
| Zeile 1: | Zeile 1: | ||
| - | {{ | + | A polynomial equation which has real coefficients always has complex conjugate roots. We can therefore say directly that the equation, in addition to the roots |
| - | < | + | <math>z=\text{2}i</math> |
| - | {{ | + | and |
| + | <math>z=-\text{1}+i</math>, has roots | ||
| + | <math>z=\overline{2i}=-2i</math> | ||
| + | and | ||
| + | <math>z=\overline{-\text{1}+i}=-1-i</math>. Because the equation is of degree 4, it does not have more than 4 roots. | ||
| + | |||
| + | The answer is thus | ||
| + | |||
| + | |||
| + | <math>\left\{ \begin{array}{*{35}l} | ||
| + | 2i \\ | ||
| + | -2i \\ | ||
| + | -1+i \\ | ||
| + | -1-i \\ | ||
| + | \end{array} \right.</math> | ||
Version vom 10:18, 28. Okt. 2008
A polynomial equation which has real coefficients always has complex conjugate roots. We can therefore say directly that the equation, in addition to the roots \displaystyle z=\text{2}i and \displaystyle z=-\text{1}+i, has roots \displaystyle z=\overline{2i}=-2i and \displaystyle z=\overline{-\text{1}+i}=-1-i. Because the equation is of degree 4, it does not have more than 4 roots.
The answer is thus
\displaystyle \left\{ \begin{array}{*{35}l}
2i \\
-2i \\
-1+i \\
-1-i \\
\end{array} \right.
