👤
a fost răspuns

Determinati. xER asfel incat:
34+15(×+3)^2=(-13)^2

^ inseamna. La puterea. 2

Răspuns :

34+15(x²+6x+9)=169
15x²+90x+9-169+34=0
15x²+90x-126=0
3(5x²+30x-42)=0
5x²+30x-42=0
Δ=900-840=60
x1=(-30+2√15)/10=2(-15+√15)/10=(-15+√15)/5
x2(-30-2√15)/10=2(-15-√15)/10=(-15-√15)/5

Alte intrebari