I agree with the above people, but I think there's a few more important things to keep in mind that will come in handy after the REU is over (I know I know, first you must get through the REU! I just wish someone had told me this when I went through mine).
1) Don't just talk to you advisor...
Thank you for your help! Using the above change of variables, I solved for x and y in terms of u and v (to compute the Jacobian \frac{∂(x,y)}{∂(u,v)} ):
v = 2xy \Rightarrow y = \frac{v}{2x}
u = x^2+y^2=x^2 + \frac{v^2}{4x^2} \Rightarrow 4x^4-4ux^2+v^2=0
Let z=x^2 . Then...
Not sure I understand that step in your picture either, but usually I think the theory of proportions refers to when to ratios are in proportion to each other, you can set them to be equal. Here's something I found with a little searching...
Homework Statement
Find the area of the plane region bounded by the curve
$$
(x^2+y^2)^3 = x^4+y^4
$$
Homework Equations
The change of variables formula:
$$
\int\int_R F(x,y)dxdy = \int\int_S G(u,v)\left| \frac{∂(x,y)}{∂(u,v)}\right| dudv
$$
The Attempt at a Solution
I...
Homework Statement
Suppose that f: [0, \infty) \rightarrow \mathbb{R} is continuous and that there is an L \in \mathbb{R} such that f(x) \rightarrow L as x \rightarrow \infty. Prove that f is uniformly continuous on [0,\infty).
2. Relevant theorems
If f:I \rightarrow \mathbb{R} is...
Homework Statement
If a and b are positive real numbers, and \lambda^{2} = ab, then \lambda = \pm \sqrt{ab}.
Homework Equations
None.
The Attempt at a Solution
This is more of a conceptual question that has always escaped me. I do not understand how the square root of two...
Hey stripes, I have a question - do you have to differentiate implicitly? If you have to find the derivative of
y=\sqrt{arctan(x)},
isn't the equation already in explicit form? (It's been a few years since calculus, so I wasn't sure). In which case, you could do the chain rule...