Reputation
19,506
Top tag
Next privilege 20,000 Rep.
Access 'trusted user' tools
Badges
1 13 39
Newest
 Yearling
Impact
~145k people reached

14h
comment How can we calculate the tensor product of Lagrange basis polynomials?
@uranix I can confirm this. You should probably make this into an answer.
1d
comment Why is reflection in a plane an automorphism?
It might be useful to add that the vector space structure is not preserved under reflection along a hyperplane unless it passes $0$. This makes clear that the definition is context-dependent since in both settings you can use $\mathbb R^n$ as the base space.
1d
comment Why is reflection in a plane an automorphism?
Does this help? You can see that for example a reflection in a vector space along a subspace is compatible with vector addition. In general an automorphism only makes sense if you have described the structure of your object.
2d
answered How to find sin and cos of 0, pi/2, pi without calculator
2d
comment How to find sin and cos of 0, pi/2, pi without calculator
These values are constants you can easily remember. What do you really want to know?
2d
comment Number of polynomial factors of $a^n-b^n$?
@wythagoras Using Lucian's remark and the well-known fact that $$x^p - 1 = (x-1)(x^{p-1} + \ldots + 1) = (x-1)\cdot \phi_p(x)$$ where $p$ is prime should prove $f(p) = 2$.
2d
revised Number of polynomial factors of $a^n-b^n$?
edited tags
2d
comment How to solve this equation numerically???
@uranix Fixed it now. Thanks again :)
2d
revised How to solve this equation numerically???
deleted 2 characters in body
2d
comment How to solve this equation numerically???
@uranix I did. Good catch for that. (+1 btw) I'll leave this inaccuracy for the moment as I don't have time now.
2d
comment How to solve this equation numerically???
@uranix How is that slow convergence? Also AFAIK the convergence is measured globally as $$\epsilon \le 2^{-k} |x - x_0|\le 2^{-k-1} (b-a)$$ Newton also only converges quadratically if the function is at least $C^1$, wich this one is not.
Jul
30
answered How to solve this equation numerically???
Jul
30
revised if the integrals of a non-negative sequence of functions go to zero, does this imply functions go to zero a.e.?
deleted 14 characters in body
Jul
30
revised if the integrals of a non-negative sequence of functions go to zero, does this imply functions go to zero a.e.?
deleted 14 characters in body
Jul
30
answered if the integrals of a non-negative sequence of functions go to zero, does this imply functions go to zero a.e.?
Jul
30
comment The Dual Problem
The conditions are equivalent to $A^T v \le 1$ and $-A^T v \ge 1$. Depending on what you have defined as your standard form, you can use this to transform the problem into standard form in some way and then apply your dual theorem. Where are you stuck?
Jul
29
revised Prove the relation for cos inverse
added 337 characters in body
Jul
29
answered Prove the relation for cos inverse
Jul
29
comment Prove the relation for cos inverse
I would try to find a geometrical representation of the sequence generated by $(x_r, x_{r+1})$ or something. I strongly suspect the infinite product comes from some iterated construction.
Jul
28
comment Taking derivate wrt a vector
For some basic information about writing math at this site see e.g. here, here, here and here.