$ \newcommand\tg{\operatorname{tg}} \newcommand\cotg{\operatorname{cotg}} \newcommand{\uhel}{{<}\kern-0.5em)\,} \newcommand\abs[1]{\left| #1 \right|} \newcommand\zav[1]{\left( #1 \right)} \newcommand\zavhra[1]{\left[ #1 \right]} \newcommand\zavslo[1]{\left\{ #1 \right\}} \newcommand\zavlom[1]{\left< #1 \, \right>} \newcommand{\podtrzeni}[1]{\underline{ #1 }} \newcommand{\vysledek}[1]{\underline{\underline{#1}}} \newcommand{\priume}[4]{ \Bigg\uparrow \underline{ \begin{array}{rp{2.3cm}r} #1 & \dots\dots\dots\dots\dots & #2 \\ #3 & \dots\dots\dots\dots\dots & #4 \end{array}} \Bigg\uparrow} \newcommand{\nepriume}[4]{ \Bigg\downarrow \underline{ \begin{array}{rp{2.3cm}r} #1 & \dots\dots\dots\dots\dots & #2 \\ #3 & \dots\dots\dots\dots\dots & #4 \end{array}} \Bigg\uparrow} \newcommand{\nepriumevpravo}[4]{ \Bigg\uparrow \underline{ \begin{array}{rp{2.3cm}r} #1 & \dots\dots\dots\dots\dots & #2 \\ #3 & \dots\dots\dots\dots\dots & #4 \end{array}} \Bigg\downarrow} $ $ \textbf{Běloun 1.3 c) / str. 7} $
Štítky: výpočty

$ \textbf{Vypočítejte} $
$$ \zav{\dfrac{1}{2}+\dfrac{1}{3}}\cdot\dfrac{2}{5}-\dfrac{3}{4} $$
$ \textbf{Řešení} $ \begin{align*} &\zav{\dfrac{1}{2}+\dfrac{1}{3}}\cdot\dfrac{2}{5}-\dfrac{3}{4} =\\ =\ &\zav{\dfrac{3+2}{6}}\cdot\dfrac{2}{5}-\dfrac{3}{4} =\\ =\ &\zav{\dfrac{5}{6}}\cdot\dfrac{2}{5}-\dfrac{3}{4} = \qquad / \, \text{zkrátíme dvěma a pěti}\\ =\ &\dfrac{1}{3}-\dfrac{3}{4} =\\ =\ &\dfrac{4-9}{12} =\\ =\ &\vysledek{-\dfrac{5}{12}} \end{align*} $ \textbf{Výsledek} $ $$ \vysledek{-\dfrac{5}{12}} $$
$ \textbf{Konec příkladu} $