已知a1,a2,a3,…,a8为各项都大于零的数列,则“a1+a8<a4+a5”是“a1,a2,a3,…,a8不是等比数列”的( )
已知函数f(x)=x﹣alnx(a∈R).
(Ⅰ)当a=2时,求曲线f(x)在x=1处的切线方程;
(Ⅱ)设函数h(x)=f(x)+1+ax,求函数h(x)的单调区间;
(Ⅲ)若g(x)=﹣1+ax,在1,e(e=2.71828…)上存在一点x0,使得f(x0)≤g(x0)成立,求a的取值范围.
To________ telling lies, he asked his friend to help him cheat his parents.( )