Question

Find the partial derivatives of f(r,s)=ln(r^2=s^2) and partial derivative of u(t,w)=te^(w/t)

Answer 1

So I solve both problems and got them right but I have a questions.

Answer 2

When solving the partial of u why does the t stay when taking respect to w?

Answer 3

and when you take the partial of f respect to s the r stays.

Answer 4

oops made a mistake up above the = sign is suppose to be a +

Answer 5

partial derivatives treats every other variable as a constant

Answer 6

yes, i know that but when taking partial of f respect to s shoudnt the r up front just go away because it's considered to be a number

Answer 7

it could be 1

Answer 8

so the answer should be 2s/(r^2+s^2) not 2rs?(r^2+s^2)