1.(x²+x-1）²-2x²-2x-1=0(x²+x-1)²-2(x²+x-1)-3=0(x²+x-1-3)(x²+x-1+1)=0(x²+x-4)(x²+x)=0x(x+1)(x²+x-4)=0x=0,x+1=0,或x²+x-4=0x²+x-4=0x=(-1±√17)/2综上x=0,x=-1,或x=(-1±√17)/22.△=(3m-1)²-4m(2m-1)=19m²-6m+1-8m²+4m=1m²-2m=0m(m-2)=0m=0(舍去)或m=2原方程为:2x²-5x+3=0(x-1)(2x-3)=0x=1或x=3/23.方程有两个不等实根,则△=(2m-3)²-4m²＞04m²-12m+9-4m²＞012m＜9m＜3/4根据韦达定理α+β=3-2mα*β=m²1/α+1/β=(α+β)/(α*β)=1α+β=α*β所以m²=3-2mm²+2m-3=0(m+3)(m-1)=0m=-3或m=1(舍去)综上,m=-3
