a)
\sqrt{128}+\sqrt{50})*\sqrt2=(8\sqrt2+5\sqrt2)*\sqrt2=13\sqrt2*\sqrt2=13*2=26
b)
\sqrt{121}-\sqrt{162}+\sqrt{200}=11-9\sqrt2+10\sqrt2=11+\sqrt2
c)
\sqrt{72}+3\sqrt{18}+\sqrt8=6\sqrt2+3*3\sqrt2+2\sqrt2=17\sqrt2
d)
(4\sqrt3+\sqrt{12}-\sqrt{75})*\sqrt3=(4\sqrt3+2\sqrt3-5\sqrt3)*\sqrt3=\sqrt3*\sqrt3=3
e)
(\sqrt2-3\sqrt3)^2=2-2*3\sqrt6+9*3=29-6\sqrt6
f)
(\sqrt5+3\sqrt2)*(\sqrt5-3\sqrt2)=5-9*2=-13