Lösung 3.1:4b
Aus Online Mathematik Brückenkurs 1
(Unterschied zwischen Versionen)
K (Lösning 3.1:4b moved to Solution 3.1:4b: Robot: moved page) |
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- | {{ | + | By writing |
- | < | + | <math>0.0\text{27 }</math> |
- | {{ | + | as |
+ | <math>\text{27}\cdot \text{1}0^{-\text{3}}</math>, where | ||
+ | <math>\text{27}=\text{3}\cdot \text{3}\cdot \text{3}=\text{3}^{\text{3}}</math> | ||
+ | and | ||
+ | <math>10^{-3}=\left( 10^{-1} \right)^{3}=0.1^{3}</math> | ||
+ | we see that | ||
+ | |||
+ | |||
+ | <math>\begin{align} | ||
+ | & \sqrt[3]{0.027}=\sqrt[3]{27\centerdot 10^{-3}}=\sqrt[3]{27}\centerdot \sqrt[3]{10^{-3}}=\sqrt[3]{3^{3}}\centerdot \sqrt[3]{0.1^{3}} \\ | ||
+ | & =3\centerdot 0.1=0.3 \\ | ||
+ | \end{align}</math> | ||
+ | |||
+ | |||
+ | where we have used | ||
+ | <math>\sqrt[3]{a^{3}}=\left( a^{3} \right)^{\frac{1}{3}}=a^{3\centerdot \frac{1}{3}}=a^{1}=a</math> |
Version vom 13:58, 22. Sep. 2008
By writing \displaystyle 0.0\text{27 } as \displaystyle \text{27}\cdot \text{1}0^{-\text{3}}, where \displaystyle \text{27}=\text{3}\cdot \text{3}\cdot \text{3}=\text{3}^{\text{3}} and \displaystyle 10^{-3}=\left( 10^{-1} \right)^{3}=0.1^{3} we see that
\displaystyle \begin{align}
& \sqrt[3]{0.027}=\sqrt[3]{27\centerdot 10^{-3}}=\sqrt[3]{27}\centerdot \sqrt[3]{10^{-3}}=\sqrt[3]{3^{3}}\centerdot \sqrt[3]{0.1^{3}} \\
& =3\centerdot 0.1=0.3 \\
\end{align}
where we have used
\displaystyle \sqrt[3]{a^{3}}=\left( a^{3} \right)^{\frac{1}{3}}=a^{3\centerdot \frac{1}{3}}=a^{1}=a