Help with Derivative Homework: f(p)/p w.r.t x,y,z

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Homework Statement



Taking the derivative of f(p)/p with respect to x,y,z separately. p = √(x^2+y^2+z^2) while f(p) is a scalar function that we don't know about

Homework Equations



f(p)/p

The Attempt at a Solution



I just wanted to know if the following is a legitimate way of doing it:

for partial derivative with respect to x: (f'(p)*pxp-f(p)*px)/p2

Similarly for derivative with respect to y: (f'(p)*pyp-f(p)*py)/p2

or is putting f'(p)*px invalid (i was thinking take the derivative of outside multiply by derivative of inside, but I'm not sure if the chain rule can be applied the way I did)
 
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hellsingfan said:

Homework Statement



Taking the derivative of f(p)/p with respect to x,y,z separately. p = √(x^2+y^2+z^2) while f(p) is a scalar function that we don't know about

Homework Equations



f(p)/p

The Attempt at a Solution



I just wanted to know if the following is a legitimate way of doing it:

for partial derivative with respect to x: (f'(p)*pxp-f(p)*px)/p2

Similarly for derivative with respect to y: (f'(p)*pyp-f(p)*py)/p2

or is putting f'(p)*px invalid (i was thinking take the derivative of outside multiply by derivative of inside, but I'm not sure if the chain rule can be applied the way I did)

Looks fine so far.
 
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