Lösung 1.3:4b
Aus Online Mathematik Brückenkurs 1
(Unterschied zwischen Versionen)
K (Lösning 1.3:4b moved to Solution 1.3:4b: Robot: moved page) |
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- | {{ | + | The numbers |
- | < | + | <math>9</math> |
- | {{ | + | and |
+ | <math>27</math> | ||
+ | can both be written as powers of | ||
+ | <math>3</math>, | ||
+ | |||
+ | |||
+ | <math>\begin{align} | ||
+ | & 9=3\centerdot 3=3^{2} \\ | ||
+ | & \\ | ||
+ | & 27=3\centerdot 9=3\centerdot 3\centerdot 3=3^{3} \\ | ||
+ | \end{align}</math> | ||
+ | |||
+ | |||
+ | Thus, all factors in the expression can be written using a common base | ||
+ | |||
+ | and the whole product can be simplified using the power rules | ||
+ | |||
+ | |||
+ | <math>\begin{align} | ||
+ | & 3^{13}\centerdot 9^{-3}27^{-2}=3^{13}\centerdot \left( 3^{2} \right)^{-3}\centerdot \left( 3^{3} \right)^{-2} \\ | ||
+ | & \\ | ||
+ | & =3^{13}\centerdot 3^{2\centerdot \left( -3 \right)}\centerdot 3^{3\centerdot \left( -2 \right)}=3^{13}\centerdot 3^{-6}\centerdot 3^{-6} \\ | ||
+ | & \\ | ||
+ | & =3^{13-6-6}=3^{1}=3 \\ | ||
+ | \end{align}</math> |
Version vom 11:48, 15. Sep. 2008
The numbers \displaystyle 9 and \displaystyle 27 can both be written as powers of \displaystyle 3,
\displaystyle \begin{align}
& 9=3\centerdot 3=3^{2} \\
& \\
& 27=3\centerdot 9=3\centerdot 3\centerdot 3=3^{3} \\
\end{align}
Thus, all factors in the expression can be written using a common base
and the whole product can be simplified using the power rules
\displaystyle \begin{align}
& 3^{13}\centerdot 9^{-3}27^{-2}=3^{13}\centerdot \left( 3^{2} \right)^{-3}\centerdot \left( 3^{3} \right)^{-2} \\
& \\
& =3^{13}\centerdot 3^{2\centerdot \left( -3 \right)}\centerdot 3^{3\centerdot \left( -2 \right)}=3^{13}\centerdot 3^{-6}\centerdot 3^{-6} \\
& \\
& =3^{13-6-6}=3^{1}=3 \\
\end{align}