(1)对函数f(x,y)=(x^2+y^2)^(x^2y^2)取对数后有 |x^2y^2ln(x^2+y^2)| ≤[(x^2+y^2)^2/4]|ln(x^2+y^2)| 而lim[(x^2+y^2)^2/4*ln(x^2+y^2)] =lim[1/4*t^2*lnt] =0 故limf(x,y) =lim(x^2+y^2)^(x^2y^2) =lime^[x^2y^2(x^2+y^2) =e^0 =1. 希望能帮到你, 望采纳. 祝学习进步