Question

对于实数a和b,定义运算“﹡”：a*b=

Answer 1

2x-1≤x-1时,即x≤0

f(x)=-(2x-1)²+2(2x-1)(x-1)-1

=-2x

2x-1>x-1时,即x>0

f(x)=(x-1)²-(2x-1)(x-1)

=-x²+x

-x²+x对称轴是x=1/2

x=1/2时,f(x)=1/4

∴0

令-x²+x=m

x²-x+m=0

韦达定理

x2x3=m

令-2x=m

x1=-m/2

x1x2x3

=-m²/2

∵0

∴m²<1/16

-1/32即x1x2x3∈(-1/32,0)

选A