f(x)=x^2-2x+3,
f(x)=(x-1)^2+2
x=-2 f(x)最大=9+2=11
x=1 f(x)最小=2
[2,11]
f(2x+1)=(2x+1)^2-2(2x+1)+3
=4x^2+4x+1-4x-2+3
=4x^2+2<3
4x^2<1
x^2<1/4
-1/2
答:
(1)f(x)=x²-2x+3=(x-1)²+2
-2<=x<=2
所以:2<=f(x)<=11
所以:f(x)的值域为[2,11]
(2)f(2x+1)=(2x+1-1)²+2=4x²+2<3
所以:x²<1/4
所以:-1/2