How do I solve this first order partial derivative problem?

[Spectre32]

We went over this breifly in class and I'm confused on it. Were doing first order only and this is the problem: z = 3x^2*y^3*e^(5x-3y) + ln(2x^2 + 3y^3) I know your susposed to Fx(x,y) and treat X or Y as a constant, depending, upon how you want to start, but I'm still unclear as to how to solve this.

Thanks for the help.

 

[fourier jr]

Well you know how to find an ordinary derivative, so if you need to get Fx, replace y by something else, like a or 17 or pi or whatever, then find the x derivative.

 

[Spectre32]

So you just single each variable out and that's it?

 

[cookiemonster]

You treat the variable you are not differentiating with respect to as any other constant, and then you differentiate normally.

Setting the variable equal to 17 or pi or something would probably confuse lots of people, though...

cookiemonster

 

[Spectre32]

yeah i was confused by that.

 

[fourier jr]

So you just single each variable out and that's it?

yeah that's it. Fix one (pretend it's constant), differentiate with respect to the other.