A200117 Decimal expansion of greatest x satisfying 2*x^2 - 2*cos(x) = sin(x).

9, 8, 4, 7, 1, 2, 6, 9, 9, 3, 6, 3, 0, 6, 7, 3, 5, 2, 4, 9, 9, 1, 3, 8, 0, 0, 9, 0, 7, 4, 8, 4, 5, 5, 2, 4, 3, 2, 3, 5, 0, 7, 8, 9, 3, 1, 1, 5, 1, 0, 5, 9, 5, 6, 0, 4, 9, 2, 5, 3, 6, 5, 5, 6, 9, 1, 3, 4, 7, 6, 9, 8, 2, 7, 3, 6, 3, 5, 2, 6, 1, 9, 1, 6, 0, 4, 3, 4, 8, 3, 7, 0, 8, 5, 6, 3, 0, 4, 0

Offset

0,1

Comments

See A199949 for a guide to related sequences. The Mathematica program includes a graph.

Links

G. C. Greubel, Table of n, a(n) for n = 0..10000

Example

least x: -0.680326414138679296239631620736419...
greatest x: 0.9847126993630673524991380090748...

Mathematica

a = 2; b = -2; c = 1;
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, -.69, -.68}, WorkingPrecision -> 110]
RealDigits[r]  (* A200116 *)
r = x /. FindRoot[f[x] == g[x], {x, .98, .99}, WorkingPrecision -> 110]
RealDigits[r]  (* A200117 *)

Prog

(PARI) a=2; b=-2; c=1; solve(x=0, 1, a*x^2 + b*cos(x) - c*sin(x)) \\ G. C. Greubel, Jun 29 2018

Crossrefs

Cf. A199949.

Sequence in context: A346931 A199862 A019720 * A019889 A243266 A358659

Adjacent sequences: A200114 A200115 A200116 * A200118 A200119 A200120

Keyword

nonn,cons

Author

Clark Kimberling, Nov 14 2011

Status

approved