如图,已知是圆的切线,切点为,交圆于点,圆的半径为2,,则的长为 .
(log23+log49+log827+…+3n)×log9=________________.
=_________________.
函数y=x,x∈(0,8)的值域是_________________.
函数y=loga(x-2)+1(a>0且a≠1)恒过定点______________.
loga<1,则a的取值范围是____________.