[m]9^{4m}\cdot 9^{-2m}=9^{4m+(-2m)}=9^{2m}[/m]
при m=0,25
[m]9^{2m}=9^{2\cdot 0,25}=9^{0,5}=3^{2})^{0,5}=3^{2\cdot 0,5}=3^{1}=3[/m]
2.1
[m](\sqrt[4]{3}-\sqrt[4]{2})\cdot (\sqrt[4]{3}+\sqrt[4]{2})\cdot (\sqrt{3}+\sqrt{2})=[/m][red][m](\sqrt[4]{3}-\sqrt[4]{2})\cdot (\sqrt[4]{3}+\sqrt[4]{2})[/m][/red][m]\cdot (\sqrt{3}+\sqrt{2})=[/m]
[red][m]=((\sqrt[4]{3})^2-(\sqrt[4]{2})^2)[/m][/red][m]\cdot (\sqrt{3}+\sqrt{2})=(\sqrt{3}-\sqrt{2})\cdot (\sqrt{3}+\sqrt{2})=(\sqrt{3}+\sqrt{2})=(\sqrt{3})^2-(\sqrt{2})^2=3-2=1[/m]