1、 设 t=2x+1
x=t-1 t和x是R
f(x)=f(t)=(t-1)^2+2*(t-1)+1/(t-1)
=自己化简
2、由f(0)=1 得 c=1
由f(x+1)-f(x)=2x 得 f(x)=f(x+1)-2x
设:x1=-1 x2=0
由：f(-1)=f(0)+2
f(0)=f(1)
得：a-b+1=3
1=a+b+1 所以a=1 b=-1
f(x)=x^2-x+1
3、设x1、x2∈(0,1)且x1>x2
f(x1)-f(x2)=x1+1/x1-x2-1/x2
=｛x1x2(x1-x2)+(x2-x1)｝/x1x2
=｛x1x2(x1-x2)-(x1-x2)｝/x1x2
=｛(x1x2-1)(x1-x2)｝/x1x2
因 0