x^2+x+1/4=0x^2+x/2+x/2+1/4=0x(x+0.5)+0.5(x+0.5)=0(x+0.5)(x+0.5)=0(x+0.5)²=0故x+0.5=0解得x=-0.5
x^2+x+1/4=0(x+1/2)^2=0x+1/2=0x=-1/2
只有一个解x=-1/2
