1. y'=(y-4x+8xy^3)/(x+12x^2y^2)
2. 2x^2yy''+y^2=x^2(y')^2
收錄日期: 2021-05-04 00:49:02
原文連結 [永久失效]:
https://hk.answers.yahoo.com/question/index?qid=20091226000010KK00111