Ajutor dau coroana si puncte ex 30

Ajutor Dau Coroana Si Puncte Ex 30 class=

Răspuns :

[tex]Stim\ ca\ (a-b)^{2}=a^{2}-2ab+b^2\\(\sqrt{5}-\sqrt{2})^{2}+2\sqrt{2}(\sqrt{5}-\sqrt{2})=\\\sqrt{5}^{2}-2\sqrt{2}*\sqrt{5}+\sqrt{2}^{2}+2\sqrt{2}*\sqrt{5}-2\sqrt{2}*\sqrt{2}=\\5-2\sqrt{10}+2+2\sqrt{10}-2\sqrt{4}=\\5+2-2*2=7-4=3[/tex]