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duki
Feb27-08, 09:32 PM
1. The problem statement, all variables and given/known data

Find \frac{dy}{dx}

2. Relevant equations

y = [cos^6 ( csc^2(4e^\pi^3))]^\frac{23}{15}

3. The attempt at a solution

so far I have \frac{23}{15}[cos^6 ( csc^2(4e^\pi^3))]\frac{d}{dx}cos^6 ( csc^2(4e^\pi^3))... but I stopped here because I don't know if I'm doing it right.

Could someone give me a hand?
1. The problem statement, all variables and given/known data



2. Relevant equations



3. The attempt at a solution

Dick
Feb27-08, 10:39 PM
There's no x in your expression at all. So dy/dx=0. This smells like a trick question.

duki
Feb27-08, 10:41 PM
HAHA! the answer was actually 0, but I had no clue how to get to it. I remember he did something on the board that I didn't get to copy down where everything ended up canceling out though.

Dick
Feb27-08, 10:58 PM
y is a constant, independent of x. Of course, dy/dx=0. You don't even have to copy anything down. The fact the expression is so ridiculously complicated should be a clue that someone is trying to pull a fast one.

duki
Feb27-08, 11:04 PM
So on the test tomorrow, if a problem like this comes up I should be safe saying:

"no 'x' expression exists, therefore dy/dx = 0."

Dick
Feb27-08, 11:09 PM
No, just say what I said. "y is a constant independent of x, so dy/dx=0". It's just like differentiating y=2. Or y=pi/3. Or y = [cos^6 ( csc^2(4e^\pi^3))]^\frac{23}{15}. They are all the same thing.

duki
Feb27-08, 11:15 PM
Alright cool. Thanks :)