2x^2+x-3=0D=1^2-4*2*(-3)=25x1=-1+5/4=1x2=-1-5/4=-6/4=-3/2=-1.5x^3=x^2-7x+7=0x^3-x^2-7x+7=0x(x^2-7)-(x^2-7)=0(x^2-7)(x-1)=0x=√ 7x=-√ 7x=1