(1)f(x)在R上有零点,当a=0时,f(x)=-2x+1,函数的零点为:
,满足题意;1 2
当a≠0时,函数f(x)=ax2-2x+1有零点,则△=4-4a≥0,解得a≤1,
∴a的取值范围:(-∞,1];
(2)∵f(x)=ax2-2x+1在[-1,0]内有零点
∴方程ax2-2x+1=0在[-1,0]内有解
即a=
=2x?1 x2
-2 x
x∈[-1,0],令1 x2
=t,1 x
t∈(-∞,-1]则a=2t-t2 t∈(-∞,-3].
∴a∈(-∞,-3].