[go: up one dir, main page]

login

Year-end appeal: Please make a donation to the OEIS Foundation to support ongoing development and maintenance of the OEIS. We are now in our 61st year, we have over 378,000 sequences, and we’ve reached 11,000 citations (which often say “discovered thanks to the OEIS”).

A200131
Decimal expansion of greatest x satisfying 2*x^2 - 4*cos(x) = 3*sin(x).
3
1, 3, 6, 8, 1, 4, 9, 1, 1, 2, 0, 4, 2, 0, 6, 7, 6, 6, 7, 9, 9, 7, 6, 9, 9, 1, 0, 8, 8, 9, 0, 6, 9, 2, 6, 6, 7, 5, 9, 0, 3, 6, 3, 8, 6, 9, 7, 9, 8, 2, 3, 5, 6, 8, 8, 7, 6, 8, 3, 8, 1, 0, 1, 7, 8, 4, 0, 2, 0, 0, 9, 5, 7, 2, 9, 5, 6, 3, 9, 7, 4, 8, 1, 6, 1, 3, 1, 7, 9, 1, 3, 4, 2, 8, 1, 1, 0, 1, 7
OFFSET
1,2
COMMENTS
See A199949 for a guide to related sequences. The Mathematica program includes a graph.
LINKS
EXAMPLE
least x: -0.719005064558842927859271780848179382...
greatest x: 1.368149112042067667997699108890...
MATHEMATICA
a = 2; b = -4; c = 3;
f[x_] := a*x^2 + b*Cos[x]; g[x_] := c*Sin[x]
Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -.72, -.71}, WorkingPrecision -> 110]
RealDigits[r] (* A200130 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.36, 1.37}, WorkingPrecision -> 110]
RealDigits[r] (* A200131 *)
PROG
(PARI) a=2; b=-4; c=3; solve(x=1, 2, a*x^2 + b*cos(x) - c*sin(x)) \\ G. C. Greubel, Jul 01 2018
CROSSREFS
Cf. A199949.
Sequence in context: A337404 A133442 A133193 * A298907 A181909 A181917
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 14 2011
STATUS
approved