Got Homework?
Connect with other students for help. It's a free community.
Here's the question you clicked on:
 0 viewing
richyw
Group Title
Find an equation for the tangent plane to the surface given by\[z=\ln{\left(1+x^2+y^2\right)}\]
 2 years ago
 2 years ago
richyw Group Title
Find an equation for the tangent plane to the surface given by\[z=\ln{\left(1+x^2+y^2\right)}\]
 2 years ago
 2 years ago

This Question is Closed

richyw Group TitleBest ResponseYou've already chosen the best response.0
Sorry, at the point (0,2,ln5). why can't I just say\[z_x=\frac{2y}{\left(1+x^2+y^2\right)}\]\[z_y=\frac{2x}{\left(1+x^2+y^2\right)}\]And then that \[zln(5)=z_x(0,2)(x0)+z_y(0,2)(y2)\]
 2 years ago

richyw Group TitleBest ResponseYou've already chosen the best response.0
so \[z=\frac{4}{5}x+\ln(5)\]
 2 years ago

richyw Group TitleBest ResponseYou've already chosen the best response.0
I don't see where I am going wrong....
 2 years ago

richyw Group TitleBest ResponseYou've already chosen the best response.0
nevermind. I see where I went wrong haha.
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.0
is it that you don't have the coefficient for z, since you didn't turn it into a function? I want to know because your way is different than mine.
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.0
er, I mean didn't turn it into a 3variable function...
 2 years ago

richyw Group TitleBest ResponseYou've already chosen the best response.0
my notation was sloppy. All I do to find the plane tangent to \(z=f(x,y)\) at the point \(P\left(a,b,f(a,b)\right)\) is use the formula \[zf(a,b)=f_x(a,b)(xa)+f_y(a,b)(yb)\]
 2 years ago

richyw Group TitleBest ResponseYou've already chosen the best response.0
I just accidentally put f_y where f_x should have been...
 2 years ago

TuringTest Group TitleBest ResponseYou've already chosen the best response.0
ah, gotchya thanks
 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.