函数和的等价性的几个定理

Some Theorems of the Equivalence of Functional Sum

两对等价函数的积商(分母不为零)仍是等价的,但它们的和不一定等价。本文给出了函数和的等价性的几个充分条件,扩大了利用等价替换求极限的范围。

The product and quotient of two equialent functions （the denominator ≠ zero） are equivalent,but their sum may not be so. This paper offers ample conditions of the equivalence of functional sum and estends the scope of seeking the limit by equivalent substitution.