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$${{\mathtt{c}}}^{{\mathtt{2}}} = {{\mathtt{a}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{{\mathtt{b}}}^{{\mathtt{2}}}$$
$${{\mathtt{a}}}^{{\mathtt{2}}} = {{\mathtt{c}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{{\mathtt{b}}}^{{\mathtt{2}}}$$
$${{\mathtt{b}}}^{{\mathtt{2}}} = {{\mathtt{c}}}^{{\mathtt{2}}}{\mathtt{\,-\,}}{{\mathtt{a}}}^{{\mathtt{2}}}$$
Beispiel: a=3 cm, b=4 cm
$${{\mathtt{c}}}^{{\mathtt{2}}} = {{\mathtt{3}}}^{{\mathtt{2}}}{\mathtt{\,\small\textbf+\,}}{{\mathtt{4}}}^{{\mathtt{2}}}$$
$${{\mathtt{c}}}^{{\mathtt{2}}} = {\mathtt{9}}{\mathtt{\,\small\textbf+\,}}{\mathtt{16}}$$
$${{\mathtt{c}}}^{{\mathtt{2}}} = {\mathtt{25}}$$
$${\mathtt{c}} = {\mathtt{5}}$$
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