||\sqrt2-3|-|4-2\sqrt2||
źródło:
\sqrt2-3\approx1,41-3\approx-1,59<0
4-2\sqrt2\approx4-2*1,41\approx4-2,82>0
||\sqrt2-3|-|4-2\sqrt2||=|-(\sqrt2-3)-(4-2\sqrt2)|=
=|-\sqrt2+3-4+2\sqrt2|=|\sqrt2-1|=+(\sqrt2+1)=\sqrt2+1