[tex]x= \sqrt{5} - \sqrt{3} \\
y= \sqrt{5}+ \sqrt{3} \\
------- \\
|x|-|y|=? \\
------- \\
|x|=| \sqrt{5}- \sqrt{3}| \\
\sqrt{5}>\sqrt{3} => \\
x= \sqrt{5}- \sqrt{3} \\ \\
y=| \sqrt{5}+ \sqrt{3}| \\
y= \sqrt{5}+ \sqrt{3} \\ \\
|x|-|y|= \sqrt{5}- \sqrt{3}-( \sqrt{5}+ \sqrt{3}) \\
= \sqrt{5}- \sqrt{3}- \sqrt{5}- \sqrt{3} \\
=-2 \sqrt{3} [/tex]