4x(x+3)=-3和3x^2-3x-1=0

问题描述:

4x(x+3)=-3和3x^2-3x-1=0

4x(x+3)=-34x^2+12x+3=0(4x+1)(x+3)=04x+1=0 或 x+3=04x=-1x1=-1/4x2=-33x^2-3x-1=0 x^2-x-1/3=0x^2-x-1/3+1/4-1/4=0(x-1/2)^2-7/12=0[x-1/2+√(7/12)][x-1/2-√(7/12)]=0x-1/2+√(7/12)=0 或 x-1/2-√(7/12...