A community for students.
Here's the question you clicked on:
 0 viewing
anonymous
 4 years ago
p
anonymous
 4 years ago
p

This Question is Closed

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0you want\[\nabla z\over\nabla x\]and\[\nabla z\over\nabla y\]?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0if you show me just one of those partial derivatives i'll know how to find the other

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0do I understand the problem correctly?

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0I don't think I do since it seems to make no sense to me...

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0the partial derivative of z with repsect to x. del z/ del x or die z / die x . that symbol that is used for partial derivatives that looks like a two kind of

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0ooooh I see, but you are not given any more info besides x=f(xy) ?

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0well then I suppose all there is to do is apply the chain rule...

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0so i can start off by going z  f(xy) = 0 then i need to find the partial derivative of x, so f_x then f_y and f_z and del z/ del x = f_x / f_z

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0do i let xy =z then use the chain rule?

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0okay I am confused again,\[z=f(xy)\]as in "z equals a function of x times y" correct?

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0actually no, i know how to do these when there are actual numbers but i'm not quite sure with the f(xy)

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0oh wait I invented a z, sorry

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0okay but this is a multiple choice question and my options are like f'(x)f(y) or xf '(xy) ect...

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0okay let me rethink this for a sec...

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0i know what i want to do but i'm not quite sure how to do it. the only thing throwing me off is f(xy) so if i take the partial derivative of that with respect to x, i hold y constant. if it was a normal expression no problem but since its not i'm a little confused

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0would it be f ' (x) f(y) ?

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0my reasoning gives\[\frac{\partial }{\partial x}z=\frac{\partial }{\partial x}f(xy)=\frac{\partial f}{\partial x}\cdot\frac{\partial }{\partial x}(xy)=y\frac{\partial f}{\partial x}=yf_x(xy)\]but the choices in your answer are for f' (whole derivatives on f, not partial)???

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0correct as in they're not partial derivatives for my choices of answers

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0so I guess then they want\[\frac{\partial }{\partial x}z=\frac{\partial }{\partial x}(xy)f'(xy)=yf'(xy)\]

TuringTest
 4 years ago
Best ResponseYou've already chosen the best response.0this would make sense, you can check it with a function like z=sin(xy), z=(xy)^2, whatever

anonymous
 4 years ago
Best ResponseYou've already chosen the best response.0if the question's asking for partial derivatives then z = f(x*y) makes sense. If the question's asking for the total differential wrt x or y than they could just be asking about the chain rule and z= f(x, y)
Ask your own question
Sign UpFind more explanations on OpenStudy
Your question is ready. Sign up for free to start getting answers.
spraguer
(Moderator)
5
→ View Detailed Profile
is replying to Can someone tell me what button the professor is hitting...
23
 Teamwork 19 Teammate
 Problem Solving 19 Hero
 Engagement 19 Mad Hatter
 You have blocked this person.
 ✔ You're a fan Checking fan status...
Thanks for being so helpful in mathematics. If you are getting quality help, make sure you spread the word about OpenStudy.