Preparing

摘要： First \[已知y=f(x) \]\[则y^{2}=f(x) \cdot f(x) \\ 则y^{2}为包含f(x)的复合函数 \\ (y^{2})'=[f^{2}(x)]' \cdot f'(x) \]\[\\ \therefore (y^{2})'=2y \cdot y' \] Second 阅读全文