C∈d=> coordonatele lui C verifica ecuatia dreptei d
2c+3c=0 => c=0 deci C (0, 0)
dreapta d este y=x prima bisectoare
Calculezi MA= d(M,A ) M(xm,ym) deoarece M∈d => xm=ym
MA=√(xm-xa)²+(ym-ya)²=√(xm-3)²+(ym-o)²=√(xm²-2xm+9+ym²)
dar xm=ym=>
MA=√2xm²-2xm +9) Sub radical ai o functie de grd 2. Aceasta are valoarea minima in -Δ/4a=-(4 -72)/4=17
MA=√17
MB =d(M ,B)=√(xm-xb)²+(ym-yb)²=√(xm²+(ym+5)²=√xm²+ym²+10ym+25
Xm=ym
MB=√2ym+10ym+25
Sub radical ai o functie de grd 2 , Punctul de minim -Δ/4a=-(100-200)/8=25/2
Mb=√25/2=5/√2
MA+MB=√17+5/√2
