- #1
1MileCrash
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Homework Statement
z = cos(x^2 + 3y^2)
x = ucosv
y=usinv
find dz/dv
Homework Equations
The Attempt at a Solution
I think I can do these fairly well, but I'm a little unsure of the "protocol" for which variables to put back in. Sometimes (in this case) I can't really put everything as v. So I choose to put everything as u and v since they are on the same "level."
for example, I get that
(dv/dv) = (dy/dv)(dz/dy) + (dx/dv)(dz/dx)
When taking those partials and multiplying out ( leaving variables as they are.. )
= - ucos(v)sin(x^2 + 3y^2)6y + usin(v)sin(x^2 + 3y^2)2x
So what is the technique? Replace all x and y with ucosv and usinv respectively, and leave u in the partial derivative?