笔者曾看到这样一本教材，在论证ｎ次代数方程有ｎ个根这一命题以及提出重根概念时，在承认代数基本定理“（复系数的）代数方程一定有根”的基础上是这样写的（大意如此）：“用归纳法证明ｎ次（ｎ≥１）代数方程有ｎ个根．当ｎ＝１即一次方程正好有一个根．现设ｎ＝ｋ时... The author once saw a textbook that, based on the proposition that n times the algebraic equation has n roots and proposed the concept of re-root, is based on the acknowledgement that the algebraic basic theorem “The algebraic equations of complex coefficients must have roots”. Written (intended to be so): "Use induction to prove n times (n ≥ 1) algebraic equations have n roots. When n = 1 the first equation has exactly one root. Now when n = k...