Find the derivative: f(x,y,z)=g(r) and r=(x^2+y^2+z^2)^(1/2)

[Apostolis]

[h=1]Hey can someone help me please with the derivative dg/dr and how to proove that formula??

If f(x,y,z)=g(r) and r=(x^2+y^2+z^2)^(1/2) proove that Δf=d^2g/dr^2 + (2/r)*dg/dr[/h]

 

[Deleted member 4993]

Hey can someone help me please with the derivative dg/dr and how to proove that formula??

If f(x,y,z)=g(r) and r=(x^2+y^2+z^2)^(1/2) proove that Δf=d^2g/dr^2 + (2/r)*dg/dr

What are your thoughts?

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[Apostolis]

Actually I don't know how I have to start
I cant find the derivative dg/dr.sorry for my English . thanks for the help
Really appreciate it

 

[Apostolis]

I haven't done any progress on that because I don't know how to begin

 

[stapel]

I haven't done any progress on that because I don't know how to begin

You original posted this to "Algebra", rather than to "Calculus". Have you studied calculus yet? Thank you!