(Ⅰ)求实数c的取值范围;
(Ⅱ)若f(x)在x=2处取得极值,且当x<0时,f(x)< 16d2 +2d恒成立,求实数d的取值范围.
— It is beside the lamp.
数列{an}的各项均为正数,Sn为其前n项和,对于任意n∈N*,总有an,Sn,an2成等差数列.
(1)求数列{an}的通项公式;
(2)设bn=1an2,数列{bn}的前n项和为Tn,求证:Tn>nn+1.