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%I #5 Mar 30 2012 18:57:53
%S 1,4,2,0,7,7,6,7,7,3,1,7,1,0,0,5,2,4,9,3,2,5,0,6,6,9,4,1,6,6,1,8,4,8,
%T 8,2,4,2,4,8,8,6,0,5,3,9,6,6,9,2,4,9,9,8,8,4,6,6,5,6,1,5,0,6,6,9,5,6,
%U 8,9,4,6,7,6,7,0,2,8,3,0,1,5,3,1,9,5,3,3,8,7,0,7,8,6,5,4,5,5,6
%N Decimal expansion of x<0 having x^2+x=4*cos(x).
%C See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e negative: -1.420776773171005249325066941661848824...
%e positive: 1.0251191119924290148461985750057832515...
%t a = 1; b = 1; c = 4;
%t f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t Plot[{f[x], g[x]}, {x, -2, 1.5}]
%t r1 = x /. FindRoot[f[x] == g[x], {x, -1.5, -1.4}, WorkingPrecision -> 110]
%t RealDigits[r1] (* A197813 *)
%t r2 = x /. FindRoot[f[x] == g[x], {x, 1, 1.1}, WorkingPrecision -> 110]
%t RealDigits[r2] (* A197814 *)
%Y Cf. A197737.
%K nonn,cons
%O 1,2
%A _Clark Kimberling_, Oct 20 2011
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