课程名称︰微积分甲下
课程性质︰数学系大一必带
课程教师︰陈荣凯
开课学院：理学院
开课系所︰数学系
考试日期（年月日）︰2014/03/06
考试时限（分钟）：30
是否需发放奖励金：是
（如未明确表示，则不予发放）
试题 :
The total is 25 points.
(1) (8 pts) Let P be a boundary point of the set S that does not belong to S.
Prove that there exists a sequence of points P , P , ... in S having P as
1 2
limit. y
x
(2) (8 pts) Find the first and second partial derivatives of e .
____
(3) (9 pts) Show that f(x, y) = √|xy| is not differentiable at (0, 0).