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Topic:
Off Topic Physics/math question
Replies:
3
Last Post:
Jan 5, 2013 12:35 PM



dy/dx
Posts:
6
Registered:
11/10/12


Re: Off Topic Physics/math question
Posted:
Jan 5, 2013 12:35 PM


On Fri, 4 Jan 2013 20:59:09 0800 (PST), wrschlanger@gmail.com wrote:
>  > If y(x) = 1 / x > then y(x) > 0 when x > 0 and y(x) < 0 when x < 0. > > According to the power rule of Calculus, y'(x) = 1 / x^2. > So y'(x) is always negative. > > Are we losing information by taking the derivative?
Yes, as evidenced by the constant of integration added going the other way.
> I think the place I make a mistake is in my understanding of how r relates to x. > If everything is oriented along the x axis, aren't they the same? Or do we have > r = x ?
The latter.



