Recent content by fuwuchen

Yes, you are right! Thanks again for your help, good luck with you!

Thank a lot for your help, Bill! But I wonder whether we can treat y as a parameter and have x = ξi(y), as in f(x,y) the two arguments x and y are independent to each other.

Hi everyone, I have trouble understanding the multiple delta function. For one dimensional delta function, we have δ(\varphi(x))=\sum_{i=1}^{N}δ(x−xi)|\varphi′(xi)| where xi's (for i = 1 to N) are simple zeros of f(x) and it is known that f(x) has no zeros of multiplicitiy > 1 but...