求解一条高数全微分题目在线等

1个回答

lnu^v=vlnu
两端对x求导得
(vlnu)'=v'lnu+v/u*u'=cosxlnlnx+sinx/lnx*(lnx)'=cosxlnlnx+sinx/(xlnx)
(u^v)'=e^[cosxlnlnx+sinx/(xlnx)]
dz=(x+u^v)'dx={1+e^[cosxlnlnx+sinx/(xlnx)]}dx