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142126
bio website math.ethz.ch/~blatter
location Switzerland
age 79
visits member for 4 years, 2 months
seen Oct 13 at 19:54

Oct
7
comment Rotational invariant curve definition
Of course this definition is clear to you, but not to the average user of MSE, like me.
Oct
7
comment Proving a function is an open map
Maybe the following is of use: A continuous bijection $f:\>X\to Y$ from a compact space (a compact neighborhood of $u$ in your case) to a Hausdorff space is a homeomorphism.
Oct
7
comment Unit Ball in 1 norm is open in ($C[0,1] , || \quad ||_{\infty}$)
I think you want $B_\infty(f,\epsilon)\subset B_1(0,1)$.
Oct
7
comment Rotational invariant curve definition
Here is a definition of twist map (it's missing in Wikipedia): mathoverflow.net/questions/89116/twist-maps-of-the-annulus
Oct
7
revised Double Integral Calculation
added 19 characters in body
Oct
7
comment Proving the differentiablity of a function.
Looking at lefthand and righthand derivatives in such an example is sick.
Oct
7
answered Double Integral Calculation
Oct
7
revised $ f^{7} $ is holomorphic implies that $ f $ is holomorphic.
added 71 characters in body
Oct
7
comment $ f^{7} $ is holomorphic implies that $ f $ is holomorphic.
@Berrick Fillmore: Thank you for the comment. I was indeed sloppy in this point. See my edit: Now there can be now mingling of different roots.
Oct
6
revised $f'(c) \ge 0 , \forall c \in (a,b)$ then $f$ is increasing in $[a,b]$ , proof of this without Mean Value theorem
added 12 characters in body
Oct
6
answered Finding more than one root using Newton's Method
Oct
6
revised $f'(c) \ge 0 , \forall c \in (a,b)$ then $f$ is increasing in $[a,b]$ , proof of this without Mean Value theorem
added 170 characters in body
Oct
6
comment $f'(c) \ge 0 , \forall c \in (a,b)$ then $f$ is increasing in $[a,b]$ , proof of this without Mean Value theorem
How do you know that $x\mapsto f(x)+\epsilon x$ is strictly increasing? If the MVT is forbidden we have to reprove it somehow.
Oct
6
answered $f'(c) \ge 0 , \forall c \in (a,b)$ then $f$ is increasing in $[a,b]$ , proof of this without Mean Value theorem
Oct
6
comment Prisoner Probability
@Math Major: It's of course $(1/3)^2(2/3)^8$ instead of $(1/3)^2+(2/3)^8$, and similarly for the other two. I thought it was just a typo; but the correct value is $0.4552$.
Oct
5
comment Prisoner Probability
You are correct with a) and b). For c) note that the "allowed" numbers of returning parolees are $2$, $3$, and $4$.
Oct
5
answered Finding the integer solutions an equation
Oct
5
answered $ f^{7} $ is holomorphic implies that $ f $ is holomorphic.
Oct
4
comment Book with novel approaches to analysis
I don't know the book, but it's approach can't be exactly novel if the author got $4$ Stalin prizes.
Oct
3
answered How did we find the solution?