Damn I kinda get stuff but others IM LOSt im only in 10th grade, Im really good at math but Ima take a calculus class next year

This.

Anyways what's the function you are derivating? f(x) = x? which means y=x if you call y your function.

So dy/dx = 1.  

But x=1 is not a function you can't derivate it.

Actually the derivative is 0.

@wfz, that would be the case if you had f(x)=1.

Yes.....if f(x) = x

and x = 1

then f(x) = 1

So I don't see what you guys are talking about..that part of his fake proof was legit. It was counting "x" as a variable that wasn't correct.

EDIT: Actually you guys just made the same mistake the fake proof does. You acted as if "x" was a variable, which it isn't in this case!

Then if x isn't a variable you can't do dy/dx as it's not a function since there's no "y".



If x=1, means that y=1 at that point.

But you can't replace the function for its value at that point before derivating.
You must derivate before replacing a value. That's the initial mistake.

Because if not you will be derivating f(x)=1 instead of f(x)=x, which are two different functions with 2 different derivates.

In the case, "x" is just another variable like "u" or "v". However we gave "x" specific terms, x = 1.

So you're saying that you derive f(x) = x and then plug in 1? No. You have to plug in the 1 first, and then derive, and the answer is 0.

Look up this problem online, I'm sure you can find it on wikipedia or something. It'll explain it for you.

Lol you can't do that, please read some math books before trying to prove me wrong.

if f(x)=x, you can't say f(x)=x=1; f(x)=x is a completely different function than f(x)=1.

Therefore their derivates will be different; in this case d(x)/dx=1 and d(1)/dx=0

You are confusing a function with the value of a function at one given point.

Your function in this case is f(x)=x, while your function at the point one f(1)=1.
When you derivate your function you get d(x)/dx = 1. Now no matter what's the value of x, the derivate will always take the value of 1. So his initial proposition was false.

If you think that what I'm saying is wrong, then prove me wrong.

Here: http://en.wikipedia.org/wiki/Invalid_proof#Proof_that_1_.3D_0

Found it for you.

If you don't understand that, then I don't know what to say. What semester/year of calculus did you say you were in again?

Lol, my point still stands. You have absolutely no idea of what you're talking about, really. You told me that it was the case of f(x)=x when I asked, so x is a variable, but now you are saying x is not a variable, you say it is a constant, therefore you contradict yourself and that shows that you don't know what you're talking about. I've proved already that what he said is wrong, I want you to prove me wrong, not to give me a solution that doesnt fit our case.

Can you do it? I guess not, because what I said is mathematically correct.

The link you gave me links me to another case, where f(x) = constant, not the case where f(x) = x like you told me when I asked.