Răspuns :
Conform formulei [tex](a-b) *(a+b)=a^{2} -b^{2}[/tex], avem:
[tex](3-\sqrt{2} )*(3+\sqrt{2} )=3^{2} -(\sqrt{2} )^{2} =9-2=7[/tex]
Conform formulei [tex](a-b) *(a+b)=a^{2} -b^{2}[/tex], avem:
[tex](3-\sqrt{2} )*(3+\sqrt{2} )=3^{2} -(\sqrt{2} )^{2} =9-2=7[/tex]