X的X次方的y次方偏导数怎么求
问题描述:
X的X次方的y次方偏导数怎么求
分别对X 和Y求偏导数,我不是很会,我求出来总是少一部分..
z=x^x^y求X和Y偏导
答
z=x^(xy) 的偏导数?两边取对数:lnz = xy lnx∂lnz/∂x = ∂z/z∂x = y(lnx+1)∂z/∂x = z(lnx+1) = x^(xy) (lnx+1)y∂lnz/∂y = ∂z/z∂y = xlnx∂z/ͦ...
不是啦,你看错题目勒是求z=x^x^y的偏导数,Y是x指数X的指数(有点绕口呵呵,我想你应该能理解)
z=x^(x^y)lnz=(x^y) lnx∂lnz/∂x=yx^(y-1) lnx + x^y/x = yx^(y-1) lnx + x^(y-1) = x^(y-1)(ylnx+1)∂lnz/∂x = (1/z)∂z/∂x = x^(y-1)(ylnx+1)∂z/∂x = x^(y-1)(ylnx+1)x^(x^y) (1)∂lnz/∂y = (1/z)∂z/∂y = lnx(x^y)lnx∂z/∂y = lnx(x^y)lnx x^(x^y) = ln²x [x^(x^y+y)] (2)