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Determinati numerele rationala a si b pentru care:

a(√5 - 2) + 2b√5 = 3(√5 - b) + 1


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[tex]a(\sqrt5-2)+2b\sqrt5=3(\sqrt5-b)+1\\ a\sqrt5-2a+2b\sqrt5=3\sqrt5-3b+1\\ a\sqrt5+2b\sqrt5-3\sqrt5=2a-3b+1\\ \sqrt5(a+2b-3)=2a-3b+1\\ \sqrt5(a+b-3)\in \mathbb{Q}\Leftrightarrow a+2b-3=0\\ \text{Deci vom avea:}\\ \left \{ {{a+2b-3=0} \atop {2a-3b+1=0}} \right. \Leftrightarrow \left \{ {{a+2b=3} \atop {2a-3b=-1}} \right. \Leftrightarrow \left \{ {{2a+4b=6} \atop {2a-3b=-1}} \right. \\ \text{Scazand relatiile obtinem:}\\ /7b=7\Rightarrow \boxed{b=1}\\ a+2=3\\ \boxed{a=1}[/tex]