\begin{eqnarray*} \dfrac{2}{x}+\dfrac{4}{x}&=&1+\dfrac{1}{x}\:/\cdot x\\[4ex]\dfrac{2x}{x}+\dfrac{4x}{x}&=&1x+\dfrac{1x}{x}\\[4ex]2+4&=&1x+1\\[2ex]6-1&=&x\\[2ex]5&=&x\end{eqnarray*}
Podmínky:
\(x \neq 0\)
Zkouška:
\begin{eqnarray*}L&=& \dfrac{2}{x}+\dfrac{4}{x}=\dfrac{2}{5}+\dfrac{4}{5}=\dfrac{2+4}{5}=\dfrac{6}{5}\\[2ex]P&=&1+\dfrac{1}{x}=1+\dfrac{1}{5}=\dfrac{5\cdot1+1}{5}=\dfrac{6}{5}\\[2ex]L&=&P\\[4ex]K&=&\lbrace5\rbrace\end{eqnarray*}