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%I #5 Mar 30 2012 18:57:57
%S 1,2,5,7,5,0,7,4,8,2,6,9,6,7,9,7,8,1,2,6,2,4,5,2,2,8,2,0,0,6,8,6,6,9,
%T 2,1,0,2,2,7,8,5,6,0,1,9,8,0,6,8,6,4,9,7,2,4,3,9,0,1,1,4,7,9,5,7,1,4,
%U 7,4,6,4,0,9,9,8,8,2,2,6,4,4,7,6,8,9,8,5,8,2,2,3,6,0,9,1,9,9,1
%N Decimal expansion of x<0 satisfying 2*x^2+3*x*cos(x)=2.
%C See A199170 for a guide to related sequences. The Mathematica program includes a graph.
%e negative: -1.25750748269679781262452282006866921022...
%e positive: 0.547005740546889576436923247150755725087...
%t a = 2; b = 3; c = 2;
%t f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c
%t Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]
%t r = x /. FindRoot[f[x] == g[x], {x, -1.3, -1.2}, WorkingPrecision -> 110]
%t RealDigits[r] (* A199275 *)
%t r = x /. FindRoot[f[x] == g[x], {x, .54, .55}, WorkingPrecision -> 110]
%t RealDigits[r] (* A199276 *)
%Y Cf. A199170.
%K nonn,cons
%O 1,2
%A _Clark Kimberling_, Nov 04 2011
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