mx^2-2(3m-1)x+9m-1=0有实数根,求m的范围
问题描述:
mx^2-2(3m-1)x+9m-1=0有实数根,求m的范围
答
[2(3m-1)]²-4m(9m-1)>=0
m不等于0
由(1)得
4(9m²-6m+1)-36m²+4m>=0
-20m>=-4
∴ma为多少,b为多少,c为多少a=mb=-2(3m-1)c=9m-1