A199621 Decimal expansion of x<0 satisfying 2*x+cos(x)=0.

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

Offset: 0

Author

Clark Kimberling, Nov 08 2011

Keywords

• nonn
• cons

Comments

See A199597 for a guide to related sequences. The Mathematica program includes a graph.

This is the abscissa point x = 0.45018... where a parabola y=x^2+a and the curve y=sin(x) touch at exactly one point, a=0.23246557... - R. J. Mathar, Aug 27 2024

Examples

			-0.450183611294873573036538696762681827320...
		

Links

• Index entries for transcendental numbers.

Crossrefs

Cf. A199597.

Programs

Mathematica

a = 2; b = 1; c = 0;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
Plot[{f[x], g[x]}, {x, -1, 1}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -.46, -.45}, WorkingPrecision -> 110]
RealDigits[r]  (* A199621 *)