Can Someone Explain How to Differentiate 3x^2 y^2 with Respect to y?

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cabellos
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Iv forgotten the basics of this. How do we go about differentiating 3x^2 y^2 w.r.t y? I know the answer is 3x^2 y^2 but could someone explain this for me please?
 
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cabellos said:
Iv forgotten the basics of this. How do we go about differentiating 3x^2 y^2 w.r.t y? I know the answer is 3x^2 y^2 but could someone explain this for me please?

You want to perform [tex]\frac{\partial}{\partial y}(3x^2y^2)[/tex].

You would simply treat the function of x as a constant and differentiate y normally, thus yielding [itex]6x^2y[/itex].

However, this is not what your answer is, so I wonder whether it is the correct question?
 
ooops I am getting myself all confused now. I know how to do partial differentiation after all. I was reading the wrong solution as the question was z = x^2 y^2 and ofcourse dz/dy would = 3x^2 y^2 !
 
cabellos said:
ooops I am getting myself all confused now. I know how to do partial differentiation after all. I was reading the wrong solution as the question was z = x^2 y^2 and ofcourse dz/dy would = 3x^2 y^2 !

Erm.. no it wouldn't.

Unless you mean z=x2y3, in which case, dz/dy would be the answer you quoted.
 
Its a big warning flag when the derivative is equal to the original function and doesn't involve e in it...