已知圆方程C1:f(x,y)=0,点P1(x1,y1)在圆C1上,点P2(x2,y2)不在圆C1上,则方程:f(x,y)﹣f(x1,y1)﹣f(x2,y2)=0表示的圆C2与圆C1的关系是( )
A:与圆C1重合
B:与圆C1同心圆
C:过P1且与圆C1圆心相同的圆
D:过P2且与圆C1圆心相同的圆
已知函数f(x)=x2+2bx,g(x)=|x﹣1|,若对任意x1,x2∈0,2,当x1<x2时都有f(x1)﹣f(x2)<g(x1)﹣g(x2),则实数b的最小值为____.
发源于青藏高原的大江大河是 ( )
— Sam has heard of this story before.
— _________.