Differentiating theta and Pi (2 Viewers)

[BlueGas]

There are lots of maxima and minima questions involving theta and pi, but I have trouble differentiating them because I don't what to do. For example this question, the same answers differentiated the equation but it's kind of confusing.

So does theta act as x?

How about Pi? That really annoys my the most, for example if I was to differentiate 2Pi, would the answer be 2? Does Pi also act x?

How about if it was 2Pir^2? As in 2 times Pi times r^2? I see this the most in cylinders, etc. How would I differentiate this?

 

[AztecWarrior]

remember that pi is a number like 90degrees, theta would act like x but in cylinders you differentiate the radius

 

[BlueGas]

remember that pi is a number like 90degrees, theta would act like x but in cylinders you differentiate the radius

So r would be the one acting as x?

 

[AztecWarrior]

yeah, but you also have to have height in terms of radius in order to differentiate the volume of a cylinder

 

[Drsoccerball]

So r would be the one acting as x?

r is constant. It depends on the question and what it says: Differentiate in terms of x means you differentiate x. Differentiate in terms of pi means you differentiate pi.

 

[Drsoccerball]

Since it's which means it's differentiating with respect to . Think of it as where and . Thus, in this case it is treated as if it were a variable.

As for we all know it's a constant so.
e.g.

But this doesnt consider : ...

 

[Silly Sausage]

Since it's which means it's differentiating with respect to . Think of it as where and . Thus, in this case it is treated as if it were a variable.

As for we all know it's a constant so.
e.g.

 

[Silly Sausage]

But this doesnt consider : ...

is not a variable unless explicitly stated otherwise.

 

[Drsoccerball]

is not a variable unless explicitly stated otherwise.

The fact that i wrote means its a variable...

 

[Silly Sausage]

There wouldn't be many cases where would be used as a variable. OP was probably getting confused on whether to treat it as a variable or a constant. If was a variable then something like .

 

[InteGrand]

 

[Silly Sausage]

lol I couldn't get latex working properly for some reason.

 

[braintic]

Just making sure that everyone realises that d/dπ is meaningless.

You can never say that d/dπ (π) is 1.

 

[InteGrand]

Just making sure that everyone realises that d/dπ is meaningless.

You can never say that d/dπ (π) is 1.

 

[calamebe]

Yeah but would you ever get an equation where pi is the variable? Likewise with e. It's pretty much a certainty that pi will never be treated as a variable.

 

[Silly Sausage]

Yeah but would you ever get an equation where pi is the variable? Likewise with e. It's pretty much a certainty that pi will never be treated as a variable.

Highly unlikely. If they do however, it will explicitly stated (or should be at least).

 

[braintic]

I realise you would never think that.
My comment was directed at HSC students with less understanding than you.
It is amazing how many people believe d/dπ (π) = 1 is a valid statement.

 

[Drsoccerball]

Yeah but would you ever get an equation where pi is the variable? Likewise with e. It's pretty much a certainty that pi will never be treated as a variable.

I've seen questions that have

 

[InteGrand]

Yeah but would you ever get an equation where pi is the variable? Likewise with e. It's pretty much a certainty that pi will never be treated as a variable.

 

[braintic]

I've seen questions that have

Example?