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A199176 Decimal expansion of x<0 satisfying x^2+2*x*cos(x)=1. 3

%I

%S 1,3,0,1,2,0,1,7,3,3,1,4,1,9,1,1,4,0,0,7,9,8,3,9,7,3,6,4,4,4,0,2,6,4,

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

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

%N Decimal expansion of x<0 satisfying x^2+2*x*cos(x)=1.

%C See A199170 for a guide to related sequences. The Mathematica program includes a graph.

%e negative: -1.301201733141911400798397364440264522...

%e positive: 0.444416809391791633213083601823107078...

%t a = 1; b = 2; c = 1;

%t f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c

%t Plot[{f[x], g[x]}, {x, -2 Pi, 2 Pi}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, -1.4, -1.3}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199176 *)

%t r = x /. FindRoot[f[x] == g[x], {x, .44, .45}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199177 *)

%Y Cf. A199170.

%K nonn,cons

%O 1,2

%A _Clark Kimberling_, Nov 04 2011

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Last modified February 25 21:55 EST 2020. Contains 332264 sequences. (Running on oeis4.)