f(x)=│x^2-1│+x^2+kx,已知函数f(x)=x^2+2/x,解不等式f(x)-f(x-1)>2x-1

问题描述:

f(x)=│x^2-1│+x^2+kx,已知函数f(x)=x^2+2/x,解不等式f(x)-f(x-1)>2x-1

先代入:x^2+2/x-(x-1)^2-2/(x-1)>2x-1 则x不等于1
展开 x^2+2/x-x^2+2x-1-2/(x-1)>2x-1
整理 2/x-2/(x-1)>0
1/x>1/(x-1)
当x>1时两边乘以(x-1)*x得
x-1>x,-1>0 无解
当x0时,两边乘以(x-1)*x得
x-1