[tex]a)E(x)=[(2x-1)+(x+1)]^2=(3x)^2=9x^2=\ \textgreater \ E(x)\vdots3[/tex]
[tex]b)a \sqrt{2} +a \sqrt{3} +b \sqrt{2} -b \sqrt{3} =3 \sqrt{2} + \sqrt{2} \\
\sqrt{2} (a+b-4)+ \sqrt{3}(a-b)=0\\
a+b-4=0=\ \textgreater \ a+b=4\\
a-b=0=\ \textgreater \ a=b=2\\
M_g= \sqrt{a\cdot b}= \sqrt{4} =2[/tex]
