- #1
Prof. 27
- 50
- 1
Homework Statement
Given: z = f(x,y) = x^2-y^2
To take the partial derivative of f with respect to x hold y constant then take the derivative of x.
∂f/∂x = 2x
What I don't understand is why such would equal 2x, when the y is still there it just isn't variable and is ignored. Wouldn't it be:
2x - y^2
where y is a constant squared?
In another example this kind of thing occurred:
z = f(x,y) = x^3*y
∂f/∂x = 3x^2*y
where y is a constant unknown.
So why the different pertaining to y in these two answers?
Thanks so much, Bertrand Russell
Homework Equations
None really.
The Attempt at a Solution
http://en.wikipedia.org/wiki/Partial_derivative
http://www.centerofmath.org/mc_pdf/sec2_1.pdf [/B]
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