Zadanie 5
|\sqrt5-\sqrt8<0 , |\sqrt5+2\sqrt8|>0
|\sqrt5-\sqrt8|-2|\sqrt5+2\sqrt8|=-(\sqrt5-\sqrt8)-2(\sqrt5+2\sqrt8)=
=-\sqrt5+\sqrt8-2\sqrt5-4\sqrt8=-3\sqrt5-3\sqrt8=-3(\sqrt5+\sqrt{4*2})=-3(\sqrt5+2\sqrt2)
Zadanie 8
log_x4=\frac{1}{2} , x>0
x^{\frac{1}{2}}=4/^2
x=16