Question: how to set variables as constants when differentiating?

Hello,

I need a little help...

what I want to do, if i have 3 equations  with multiple variables and i want to get derivative of some of these variables wrt other variables while setting others as constants

here in the example

1st i thought the last equation should have partial m / partial f ... how can i get that

2nd if ,another problem, i wanted to set z as a constant so it won't consider getting its derivative, how do i get that

diff_test.mw

f1 := x = y+z

x = y+z

(1)

f2 := y = 2*f^2+3

y = 2*f^2+3

(2)

f3 := z = 22*f^3+33*f+m

z = 22*f^3+33*f+m

(3)

implicitdiff({f1, f2, f3}, {x, y, z}, x, f)

66*f^2+4*f+33

(4)

NULL


Download diff_test.m

 

hope i was clear in my explanation. thank you

 

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