A200106 Decimal expansion of greatest x satisfying x^2 - 4*cos(x) = 4*sin(x).

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

Offset: 1

Author

Clark Kimberling, Nov 13 2011

Keywords

• nonn
• cons

Comments

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

Examples

			least x: -0.698933604732903309337989544733567956233...
greatest x: 1.7695688743727017491150784620016277547...
		

Links

• G. C. Greubel, Table of n, a(n) for n = 1..10000
• Index entries for transcendental numbers.

Crossrefs

Cf. A199949.

Programs

Mathematica

a = 1; b = -4; c = 4;
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, -.7, -.6}, WorkingPrecision -> 110]
RealDigits[r]  (* A200105 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.76, 1.77}, WorkingPrecision -> 110]
RealDigits[r]  (* A200106 *)

PARI

a=1; b=-4; c=4; solve(x=1, 2, a*x^2 + b*cos(x) - c*sin(x)) \\ G. C. Greubel, Jun 25 2018