We could use:
[tex](a-b)(a+b)=a^2-b^2[/tex]
For the first and third factors there will be:
[tex](\sqrt{3755}+\sqrt{3752})(\sqrt{3755}-\sqrt{3752})=(\sqrt{3755})^2-(\sqrt{3752})^2=\\\\3755-3752=3[/tex]
and for the second and fourth:
[tex](-\sqrt{3755}-\sqrt{3752})(\sqrt{3752}-\sqrt{3755})=\\\\=
(-\sqrt{3755}-\sqrt{3752})(-\sqrt{3755}+\sqrt{3752})=\\\\=
(-\sqrt{3755})^2-(\sqrt{3752})^2=3755-3752=3[/tex]
So the answer is:
[tex]3\cdot 3=\boxed{9}[/tex]
