Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
How do I partially differentiate f = 2x/(x^2 +y^2) wrt x and y?
Is it by the quotient rule? Any help is very much appreciated.
 2 years ago
 2 years ago
How do I partially differentiate f = 2x/(x^2 +y^2) wrt x and y? Is it by the quotient rule? Any help is very much appreciated.
 2 years ago
 2 years ago

This Question is Closed

experimentXBest ResponseYou've already chosen the best response.0
by treating one as constant
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
quotient rule needed for \(f_x\) but not for \(f_y\) since in that case you view \(2x\) as a constant
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
who nellie, you are differentiating not integrating.
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
\[f_x=\frac{(x^2+y^2)2x^2(2x)}{(x^2+y^2)^2}\] then some algebra to clean it up
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
\(f_y\) is easier because you treat the numerator as a constant you get \[f_y=\frac{2y}{(x^2+y^2)^2}\]
 2 years ago

kingdan1550Best ResponseYou've already chosen the best response.0
I ended up getting 2/(x^2 + y^2)  4x^2/(x^2 +y^2)^2 for the partial derivative wrt x and 4yx/(x^2 +y^2) for y. Any idea where I might be going wrong? Thanks again
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
maybe i made a mistake. lets do it for \(f_y\)
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
oh right, doh you are rigth about \(f_y\)
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
well, except the denominator should be squared
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
or in this case just \[\frac{d}{dy}\frac{1}{f(y)}=\frac{f'(y)}{f^2(y)}\]
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
first one it looks like you are using the product rule, so i might be the same as my answer
 2 years ago

satellite73Best ResponseYou've already chosen the best response.1
oh yes, you are right. i missed a 2 from the 2x up top you are correct
 2 years ago

kingdan1550Best ResponseYou've already chosen the best response.0
Ah, fantastic. Thanks a million.
 2 years ago
See more questions >>>
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.