高数微分习题求下列各函数的微分dy(1)y=3x^2-ln 1/x(2)y=e^-x cosx设由下列方程确定y是x的函数,求dy(1)2x^2 y-xy^2 +y^3=0

来源:学生作业帮助网 编辑:作业帮 时间:2024/11/20 11:43:15
高数微分习题求下列各函数的微分dy(1)y=3x^2-ln 1/x(2)y=e^-x cosx设由下列方程确定y是x的函数,求dy(1)2x^2 y-xy^2 +y^3=0
xRMo@+Hlg^۱Q {i ml v9VTQȯ/]Ǥ@'{޼yؽy|Z̫gW?̖WΪ7ՋwOjmʈcL@-X^E=|}tz?r9"Z$-!іC^rD?siƟj%f#%+.EH >M݆W_p xd M%_W!k)h@q@W5tLK:bpp!AnDl `8RD=:p4%6"*.x_.\FhP;ZjG1mL4tOsT;2je%nEtZƘuY1ΧyI??g< e?(.:Os\/ mfĵk

高数微分习题求下列各函数的微分dy(1)y=3x^2-ln 1/x(2)y=e^-x cosx设由下列方程确定y是x的函数,求dy(1)2x^2 y-xy^2 +y^3=0
高数微分习题
求下列各函数的微分dy
(1)y=3x^2-ln 1/x
(2)y=e^-x cosx
设由下列方程确定y是x的函数,求dy
(1)2x^2 y-xy^2 +y^3=0

高数微分习题求下列各函数的微分dy(1)y=3x^2-ln 1/x(2)y=e^-x cosx设由下列方程确定y是x的函数,求dy(1)2x^2 y-xy^2 +y^3=0
(1)y = 3x^2 - ln 1/x = 3x^2 + lnx
dy = 6xdx + (1/x)dx
=(6x + 1/x)dx
(2)y = e^(-x)cosx
dy = -e^(-x)cosxdx - e^(-x)sinxdx
= -e^(-x)[cosx + sinx]dx
(3)2x^2 y - xy^2 + y^3=0
4xydx + 2x^2dy - y^2dx - 2xydy + 3y^2dy = 0
dy = [4xy - y^2]dx/[2xy - 3y^2 - 2x^2]
= [(4x - y)y/(2xy - 3y^2 - 2x^2)]dx

(1)dy=6x+1/x
(2)dy=sinxe^(-x)-cosxe^-x
(3)dy=(y^2-4xy)/(2x^2+3y^2-2xy)

如图