Question

Aratati ca nr urmatoare sunt patrate perfecte: a7 ×a9+1 ;

Aflati x si y apartine R stiind ca: x la puterea 2 +(y-2) la puterea 2 =0

Answer 1

1)a7 ×a9+1=(10a+7)(10a+9)+1=100a²+90a+70a+63+1=100a²+160+64=(10a+8)²

2)x²+(y-2)²=0
x²=0⇒x=0
(y-2)²=0⇒y-2=0⇒y=2.