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Dec
11
comment Roll one ellipse on another: Locus of center ever a circle?
Good thing I found this question, then. :)
Dec
10
awarded  Revival
Dec
10
revised Spherical Bessel Zeros
added 1 character in body; edited title
Dec
10
comment Roll one ellipse on another: Locus of center ever a circle?
Bonus: the usual lemniscate of Bernoulli can be obtained as the trace of the center of an equilateral hyperbola rolling on a congruent hyperbola. (In fact, the Booth lemniscates in general are defined as the pedal curves of a central conic.)
Dec
10
comment Roll one ellipse on another: Locus of center ever a circle?
Its parametric equations will certainly involve the incomplete elliptic integral of the second kind; that much is certain.
Dec
10
comment Roll one ellipse on another: Locus of center ever a circle?
@Tony, actually, nothing in the usual definition of a "roulette" says that the point should be on the circumference. Thus, both cycloids and trochoids are considered roulettes, to use the classical example.
Dec
10
answered Roll one ellipse on another: Locus of center ever a circle?
Dec
10
comment Focus of a rolling parabola traces a catenary - geometric explanation
Possible duplicate of Why does the focus of a rolling parabola trace a catenary?
Dec
10
revised Spherical Bessel Zeros
added 6 characters in body
Dec
10
comment Spherical Bessel Zeros
...and how exactly did you think were these computed internally by Mathematica, by the swish of a unicorn's tail?
Dec
7
awarded  Popular Question
Dec
4
awarded  Popular Question
Dec
3
awarded  Nice Answer
Nov
30
revised Why in an inconsistent axiom system every statement is true? (For Dummies)
added 2 characters in body
Nov
30
awarded  Enlightened
Nov
29
awarded  Nice Answer
Nov
26
comment Why does this matrix give the derivative of a function?
I think this is the answer I like the most. It is noteworthy that all your extended numbers map to equivalent Toeplitz matrices.
Nov
25
revised Integral representation of the modified Bessel function involving $\sinh(t) \sinh(\alpha t)$
edited tags
Nov
24
awarded  Nice Answer
Nov
23
revised Is there any proof that the Riemann Zeta function is not elementary?
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