Determinati a,b ∈ R, astfel incat [tex] \sqrt{a-1} [/tex] + 2 [tex] \sqrt{b-2} [/tex] = [tex] \frac{a+b+2}{2} [/tex]

Răspuns :

Notam √(a-1)=x si √(b-2)=b.
Ecuatia se scrie:
x+2y=(x²+1+y²+2+2)/2⇒
x²+y²-2x-4y+5=0⇒
(x-1)²+(y-2)²=0⇒x=1 si y=2⇒
√(a-1)=1⇒a=2
√(b-2)=2⇒b=6