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Variational calculus

1. The problem statement, all variables and given/known data

Question:

If ##r_+ \neq r_{++}## and ## g(r=r_+) \neq g(r=r_{++}) ##

When is it fulfilled that ## d g (r=r_+) \neq d g (r=r_+) ## ?

2. Relevant equations
##r_+ \neq r_{++}##
## g(r=r_+) \neq g(r=r_{++}) ##

3. The attempt at a solution

I tried computing ## dg(r_+) = \frac{\partial g}{\partial r} \Big |_{r=r_+} dr_+##, but i am very confused. This is all the information that i have of this problem.
 

WWGD

Science Advisor
Gold Member
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Can you define #r_{+} , r_{++}## for us? Do it through a forehand or backhand, either is OK ;).
 
Can you define #r_{+} , r_{++}## for us? Do it through a forehand or backhand, either is OK ;).
I dont understand your assumption. ##r=r_+## and ##r=r_{++}## are two differents points such that ##r_{++}>r_+##
 

WWGD

Science Advisor
Gold Member
4,137
1,726
I dont understand your assumption. ##r=r_+## and ##r=r_{++}## are two differents points such that ##r_{++}>r_+##
Sorry, a tennis joke; guess you're tired of them ;).
 

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