Question

1、m取何值时,方程3x^2-2(3m+1)x+3m^2-1=0有重根

Answer 1

^2-4ac=0

1)[-2(3m+1)]^2-12(3m^2-1)=0

m=2/3

2)144-16k=0

k=9

4a^2k^2-4k(a+2)=0

k=0,k=(a+2)/a^2,

a=0,k