Lösung 2.1:3d
Aus Online Mathematik Brückenkurs 2
(Unterschied zwischen Versionen)
K (Lösning 2.1:3d moved to Solution 2.1:3d: Robot: moved page) |
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| - | {{ | + | By dividing the two terms in the numerator by |
| - | < | + | <math>x</math>, we can simplify each term to a form which makes it possible simply to write down the primitive functions of the integrand: |
| - | {{ | + | |
| + | |||
| + | <math>\begin{align} | ||
| + | & \int{\frac{x^{2}+1}{x}}\,dx=\int{\left( \frac{x^{2}}{x}+\frac{1}{x} \right)}\,dx \\ | ||
| + | & =\int{\left( x+x^{-1} \right)}\,dx \\ | ||
| + | & =\frac{x^{2}}{2}+\ln \left| x \right|+C \\ | ||
| + | \end{align}</math> | ||
| + | |||
| + | |||
| + | where | ||
| + | <math>C</math> | ||
| + | is an arbitrary constant. | ||
| + | |||
| + | NOTE: observe that | ||
| + | <math>\frac{1}{x}</math> | ||
| + | has a singularity at | ||
| + | <math>x=0</math>, so the answers above are only primitive functions over intervals that do not contain | ||
| + | <math>x=0</math>. | ||
Version vom 13:57, 17. Okt. 2008
By dividing the two terms in the numerator by \displaystyle x, we can simplify each term to a form which makes it possible simply to write down the primitive functions of the integrand:
\displaystyle \begin{align}
& \int{\frac{x^{2}+1}{x}}\,dx=\int{\left( \frac{x^{2}}{x}+\frac{1}{x} \right)}\,dx \\
& =\int{\left( x+x^{-1} \right)}\,dx \\
& =\frac{x^{2}}{2}+\ln \left| x \right|+C \\
\end{align}
where
\displaystyle C
is an arbitrary constant.
NOTE: observe that \displaystyle \frac{1}{x} has a singularity at \displaystyle x=0, so the answers above are only primitive functions over intervals that do not contain \displaystyle x=0.
