Optimization Quick Problem
Hello guys, quick question. I'm attempting to optimize the surface area of a frustum but I'm having trouble understanding how to get from one step to another. Could anyone please explain why this person chose to change the variables (r,R,h) and how they deduced the substitutions? Here's the link:
https://math.stackexchange.com/questions/4024363/optimizingaconicalfrustumusingpartialdifferentiation/4024472#4024472
/>
Thanks
Answer
Answers can only be viewed under the following conditions:
 The questioner was satisfied with and accepted the answer, or
 The answer was evaluated as being 100% correct by the judge.
Erdos
4.7K

Thank you so much, I really appreciate it.
The answer is accepted.
Join Matchmaticians Affiliate Marketing
Program to earn up to a 50% commission on every question that your affiliated users ask or answer.
 answered
 641 views
 $9.84
Related Questions
 Convergence of $\sum\limits_{n=1}^{\infty}(1)^n\frac{n+2}{n^2+n+1}$
 Urgency Can you help me Check these Applications of deritive.
 Fermat's method of calculus
 Function Invertibility/Inverse & Calculus, One question. Early Uni/College level
 TrueFalse real analysis questions
 Early uni/college Calculus (one question)
 Calculus Questions
 Evaluate $\int \ln(\sqrt{x+1}+\sqrt{x}) dx$
So you just need an explanation for the change the variables (r,R,h) and how the substitution is done?
Yes, I need the explanation for the change of variables, and why he chose those values. It just seems kind of random to throw sin and cos in there, and I haven't been able to find an explanation for it.