跪求极限Y=lim (xy+1)/x^4+y^4,当(x,y)→(0,0),
问题描述:
跪求极限Y=lim (xy+1)/x^4+y^4,当(x,y)→(0,0),
答
Y=lim (xy+1)/x^4+y^4=lim (xy+1)/lim (x^4+y^4) 又(x,y)→(0,0),则有:lim (xy+1)=1,(x^4+y^4)∈(0,1)Y=lim (xy+1)/x^4+y^4=lim (xy+1)/lim (x^4+y^4)=∞(当(x,y)→(0,0)时)...