若函数f(x)=a2x2(a>0),g(x)=blnx.(1)若函数y=f(x)图像上的点到直线x-y-3=0距离的最小

f(x)上的点到x-y-3=0的距离＝｜x-a^2x^2-3|/根号2＝｜a^2x^2-x+3|/根号2
a^2x^2-x+3=a^2(x-1/2a^2)+3-1/(4a^2)
当x=1/(2a^2)时有最小值是3-1/(4a^2)
即|3-1/4a^2|/根号2＝根号2
｜3-1/4a^2|=2
3-1/4a^2=2或－2
1/4a^2=1或5
4a^2=1或1／5
a>0,则a=1/2或根号5／10