22.對(duì)于函數(shù)f(x),若存在x
0∈R,使f(x
0)=x
0成立,則稱x
0為f(x)的不動(dòng)點(diǎn).已知函數(shù)f(x)=mx
2+(n-1)x+n-8(m≠0).
(1)當(dāng)m=1,n=0時(shí),求函數(shù)f(x)的不動(dòng)點(diǎn);
(2)若對(duì)任意實(shí)數(shù)n,函數(shù)f(x)恒有兩個(gè)相異的不動(dòng)點(diǎn),求實(shí)數(shù)m的取值范圍;
(3)若f(x)的兩個(gè)不動(dòng)點(diǎn)為x
1,x
2,且
,當(dāng)1<m<3時(shí),求實(shí)數(shù)n的取值范圍.