题目3.单选题lim_((x,y)to(0,0))(sin(x^3+y^3))/(x+y)=( )A. 1B. 0C. 不存在D. 0或13.单选题 $\lim_{(x,y)\to(0,0)}\frac{\sin(x^{3}+y^{3})}{x+y}=$ ( )A. 1B. 0C. 不存在D. 0或1题目解答答案B. 0