(1)设f(x)=ax^2+bx+c(a≠0)
f(0)=c=1
f(x+2)-f(x+1)=2ax+3a+b=2x+1
2a=2,3a+b=1
a=1,b=-2
即f(x)=x^2-2x+1
(2)f(x)=x^2-2x+1=(x-1)^2
f(x)max=f(-1)=4
f(x)min=f(1)=0
(1)设f(x)=ax^2+bx+c(a≠0)
f(0)=c=1
f(x+2)-f(x+1)=2ax+3a+b=2x+1
2a=2,3a+b=1
a=1,b=-2
即f(x)=x^2-2x+1
(2)f(x)=x^2-2x+1=(x-1)^2
f(x)max=f(-1)=4
f(x)min=f(1)=0