推 DDGregorius : 感謝 p幣晚上給 05/14 09:07
※ 引述《DDGregorius (Next Jeter)》之銘言：
: 1.
: if cos(xyz)=1+x^2y^2+z^2,find dz/dy?
: 2.
: find dz/dx and dz/dy if x^2+2y^2+3z^2=1
: 過程要怎麼寫啊？有請大神
1.
let F(x,y,z) = 1 + x^2y^2+z^2 - cos(xyz)
dz/dy = - Fy / Fz
2 x^2 y + xz * sin(xyz)
= - ------------------------
2z + xy * sin(xyz)
2. let F(x,y,z) = x^2+2y^2+3z^2 - 1
dz / dx = - Fx / Fz
= - 2x / 6z = - x/3z
dz / dy = - Fy / Fz = - 4y/6z = - 2y / 3z
有錯還請不吝指正。
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