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[Fourier Series] Find the exponential/trigonometric series of the even part of the function.

[College Trigonometry] Getting Conflicting Answers on Law of Cosines Question

Author : Orangematz

Subreddit : learnmath

Points : 1

Published : 5 hours ago

Comments : 5

How to actually solve problems?

how would you solve this equation?

Author : Bygfvcffcvgy

Subreddit : learnmath

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Published : 3 hours ago

Comments : 2

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Author : chicagonomics

Subreddit : learnmath

Points : 1

Published : 1 hour ago

Comments : 1

Calculus 3 - Any advice for how to draw regions of space?

Author : LowerDelivery

Subreddit : learnmath

Points : 2

Published : 1 hour ago

Comments : 3

Combinatorics Problem

Author : thegoatofdover

Subreddit : learnmath

Points : 2

Published : 1 hour ago

Comments : 9

Derivatives

Good calculator apps?

Author : TAFKAMoistowelettes

Subreddit : learnmath

Points : 1

Published : 20 minutes ago

Comments : 3

## firstdwarf

Let’s begin with the formula for volume and surface area: V = (4/3) π r

^{3}and S = 4 π r^{2.}You’re going to want to take the derivative of those two with respect to time. Note that by the chain rule, a function of r given by f(r) has the derivative (df/dr) (dr/dt). You should find that dV/dt = 4 π r^{2}dr/dt and dS/dt = 8 π r dr/dt. Now simply compare their formulas to identify whatever relationships you’d like!## [deleted]

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## firstdwarf

Several ways. From the way you wrote the question, I’m assuming you don’t want your answer to depend on dr/dt, so solve both of those equations for dr/dt and then set them equal to each other. This will give you a direct relationship, but it’s up to you what to do with it. You can solve for one in terms of the other, find their proportion, or whatever else.

## jdorje

S = dV/dr

So if you take d/dt on both sides then...?