Odpowiedź:
[tex](\sqrt{2}+\sqrt{8})^2=(\sqrt{2})^2+2\cdot\sqrt{2}\cdot\sqrt{8}+(\sqrt{8})^2=2+2\sqrt{16}+8=2+2\cdot4+8=\\\\=2+8+8=18\\\\lub\\\\(\sqrt{2}+\sqrt{8})^2=(\sqrt{2}+\sqrt{4\cdot2})^2=(\sqrt{2}+2\sqrt{2})^2=(3\sqrt{2})^2=3^2\cdot(\sqrt{2})^2=9\cdot2=18\\\\\\\\(3+\sqrt{5})^2=3^2+2\cdot3\sqrt{5}+(\sqrt{5})^2=9+6\sqrt{5}+5=14+6\sqrt{5}\\\\\\(3-2\sqrt{3})^2=3^2-2\cdot3\cdot2\sqrt{3}+(2\sqrt{3})^2=9-12\sqrt{3}+4\cdot3=9-12\sqrt{3}+12=21-12\sqrt{3}[/tex]
[tex]Zastosowane\ \ wzory\\\\(a+b)^2=a^2+2ab+b^2\\\\(a-b)^2=a^2-2ab+b^2[/tex]
