y=f(x)(x≠0)是奇函数,且当x属于(0,+∞)时是增函数,若f(1)=0,求不等式f[x(x-1\2)]<0解集
问题描述:
y=f(x)(x≠0)是奇函数,且当x属于(0,+∞)时是增函数,若f(1)=0,求不等式f[x(x-1\2)]<0解集
答
f[x(x-1/2)]0
f[x(x-1/2)]>f(1)
f(x)在0,+∞)时是增函数
所以 x(x-1/2)>1
x²-(1/2)x-1>0
2x²-x-2>0
x>(1+√17)/4或x0
f[x(x-1/2)]>0
-f[-x(x-1/2)]>0
f[-x(x-1/2)]答案是1\2<1+√7/4或1-√7/4<x<0晕菜,我按大于0做了,抱歉f[x(x-1/2)]0 f[x(x-1/2)]