Recent content by frb

of course. My brain is fried due to too much studying. I tend to make things more difficult then. I thought that there should be a flaw or something. Thanks though!

Suppose I have proven the statement f(x) = n implies g(x)=n. To obtain equivalence I have to prove f(x) != n implies g(x) != n. So i reason as follows, suppose f(x) != n, f(x) surely has another value, let this value be m, so f(x) = m, and m != n. f(x) = m implies g(x) = m, and that implies...

of course it is not a proof, it can give an indication that the theorem might be true and give you a reason to find a formal proof. for example the difference of the partial sums might eventually be smaller than some epsilon, but it might also always be larger than some lower bound some ideas...

Suppose I want to show that two functions f and g are equal. A way to prove this could be to prove the statement: f(x) = n \Leftrightarrow g(x) = n Is it enough to show one side of the implication? Prove the following statement: f(x) = n \Rightarrow g(x) = n and reason as follows...

what does \frac{\partial{f}}{\partial{u}} mean? Is the following formula correct? \frac{\partial{h}}{\partial{x}}(a,b)=\frac{\partial{f}}{\partial{x}}(u(a,b),v(a,b))\frac{\partial{u}}{\partial{x}}(a,b)+\frac{\partial{f}}{\partial{y}}(u(a,b),v(a,b))\frac{\partial{v}}{\partial{x}}(a,b)

If I have a function f from RxR to R, and a function g from RxR to RxR. What are the partial derivatives of the composition f(g)? I end up multiplying the derivative of f with g, but g is a vector? The partial derivative should have its image in R.

No, but I was trying to avoid resorting to mere number crunching. Seems like there is no other way...

Let V be the variety of the ideal (f) a singular point is a point where all the partial derivatives of the f are zero. I know you can find singular points by writing down all these partial derivatives and also that the points are zeros of f (such as all points on the variety) and solve that...

I get it, thanks for helping.

thank you very much

can someone explain this proof please, I added a star to the inequalities I don't see/understand. if | | is a norm on a field K and if there is a C > 0 so that for all integers n |n.1| is smaller than or equal to C, the norm is non archimedean (ie the strong triangle inequality is true)...

can someone explain this proof please, I added a star to the inequalities I don't see/understand. if | | is a norm on a field K and if there is a C > 0 so that for all integers n |n.1| is smaller than or equal to C, the norm is non archimedean (ie the strong triangle inequality is true)...

Can anyone recommend me some good titles in this sereis about mathemathics and theoretical physics. I'm a college student and I just want to buy some for extra information. And has anyone used the Schaum's Outline of Calculus? I was looking into buying it, but I read a review that said the book...

can anyone explain me the technique to decompose a random n-cycle into a bucnh of 2 cycles. Thanks in advance.

is it, cause velocity isn't.