A:k>0
B:k<0
C:k>1
D:k<1
函数y=log2x-12x的零点个数是( )
在等比数列{an}中,a3=32,S3=92.
(Ⅰ)求{an}的通项公式;
(Ⅱ)记bn=log26a2n+1,且{bn}为递增数列,若Cn=1bnbn+1,求证:C1+C2+C3+…Cn<14.