A.高阶无穷小
B.低阶无穷小
C.等价无穷小
D.同阶但非等价无穷小
设a(x)=1-cosx,β(x)=2x2,则当x—0时,下列结论中正确的是()。A.a(x)与β(x)是等价无穷小B.a(x)是β(x)是高价无穷小C.a(x)是β(x)是低价无穷小D.a(x)是β(x)是同价无穷小但不是等价无穷小