楼上说错了 其实是已知当x→0时,lim[xsin(1/x)]=0,所以 lim(xsin*2/x+2/x*sinx) =lim(xsin*2/x)+lim(2/x*sinx) =2lim[(x/2)sin*2/x]+2lim(sinx/x) =0+2 =2
