求第三题详解。
展开全部
设f(x)=y,
φ(x)=(1+y'dx/y)^(x/dx)
=e^(x y'/y),
φ'(x)=e^(xy'/y)×(y'/y-xy'²/ y²),
即φ'(x)=e^[xf'(x)/f(x)]×{f'(x)/f(x)+x[f'(x)]²/f²(x)}φφ
φ(x)=(1+y'dx/y)^(x/dx)
=e^(x y'/y),
φ'(x)=e^(xy'/y)×(y'/y-xy'²/ y²),
即φ'(x)=e^[xf'(x)/f(x)]×{f'(x)/f(x)+x[f'(x)]²/f²(x)}φφ
追答
设f(x)=y,
φ(x)=(1+y'dx/y)^(x/dx)
=e^(x y'/y),
φ'(x)=e^(xy'/y)×(y'/y-xy'²/ y²),
即φ'(x)=e^[xf'(x)/f(x)]×{f'(x)/f(x)+x[f'(x)]²/f²(x)}
推荐律师服务:
若未解决您的问题,请您详细描述您的问题,通过百度律临进行免费专业咨询