3x²+2x-3=0x²+2x/3-1=0x²+2x/3+1/9=10/9(x+1/3)²=10/9x=-1/3-(√10)/3或x=-1/3+(√10)/3
解 3x^2+2x-3=0 x^2-(2/3)x-1=0 x^2-(2/3)x+1/9-1/9-1=0 (x-1/3)^2=10/9 x-1/3=±√10/3 x1,2=(1±√10)/3