因x^2+y^2≥2|xy|,所以
0≤|(x+y)/(x^2-xy+y^2)|
≤|x+y|/(x^2+y^2-|xy|
≤|x+y|/|xy|
≤1/|x|+1/|y|
且lim(1/|x|+1/|y|)=0
故lim[(x+y)/(x^2-xy+y^2)]=0.
lim(x→∞,y→∞) x+y/x^2-xy+y^2
2个回答
相关问题
-
Lim(x+y)/(x2-xy+y2) (x,y)→(∞,∞)这个怎么算
-
求lim(x→0,y→1)(1-xy)/(x2+y2)=____
-
lim（x→0）（3xy/（x^2+y^2））
-
求极限lim「xy／（x^2+y^2）」^（x^2） （x,y）趋向于正无穷
-
大家看看有什么区别lim lim [(x^2-y^2)/(x^2+y^2)]y-0 x-0lim lim [(x^2-y
-
(x-y)[(x+y)^2-xy]+(x-y)[(x-y)^2+xy]
-
求下列各极限 lim(x,y)→(0,1) (2-xy)/(x^2+2y)
-
(x-y)(x2+xy+y2)-xy(y-x)
-
x2+2xy+y2x2y+xy2−x2−2xy+y2x2y−xy2．
-
极限limxy/(x+y)=?x→0,y→0,lim(xy)/(x+y)=?