填空

设y=fx二阶可导f’x≠0它的反函数是x=φy又f0=1f’0=f0=-1则=______．

设a为常数则数列极限=______．

设y=sin4x则yn=______．

设fx在[0+∞连续在0+∞可导x∈0+∞时fx＞0且单调上升x=gy为y=fx的反函数它们满足则f

设fu连续且duxy=fxyydx+xdy则uxy=______．