当x→0时 sinx与x为同阶无穷小量 ∴当x→0,y→2时即xy→0 sinxy/xy→1 极限值=2还是不太懂啊
lim x→0y→2 sin(xy)/x
=lim x→0y→2 (xy)/x
=lim x→0y→2 y
= 2sinxy/x=(sinxy/xy)y当x→0,y→2时 sinxy/xy→1∴(sinxy/xy)y→y→2