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%I #7 Aug 09 2021 07:39:57
%S 8,5,8,7,6,9,7,1,3,6,9,7,6,1,4,4,2,1,1,9,3,1,0,4,3,2,1,8,1,0,5,3,3,0,
%T 8,6,1,1,8,5,6,5,7,7,3,4,6,8,7,1,4,7,4,5,8,5,1,7,3,6,1,6,4,0,8,0,2,9,
%U 2,2,0,6,4,7,4,8,6,2,6,4,9,1,8,0,5,9,3,4,3,9,1,7,6,5,9,0,5,9,9
%N Decimal expansion of least x having 2*x^2-4x=-3*cos(x).
%C See A197737 for a guide to related sequences. The Mathematica program includes a graph.
%e least x: 0.85876971369761442119310432181053308611...
%e greatest x: 2.4766169740668170810192726417322477...
%t a = 2; b = -4; c = -3;
%t f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
%t Plot[{f[x], g[x]}, {x, -1, 3}]
%t r1 = x /. FindRoot[f[x] == g[x], {x, .85, .86}, WorkingPrecision -> 110]
%t RealDigits[r1] (* A198136 *)
%t r2 = x /. FindRoot[f[x] == g[x], {x, 2.4, 2.5}, WorkingPrecision -> 110]
%t RealDigits[r2] (* A198137 *)
%Y Cf. A197737.
%K nonn,cons
%O 0,1
%A _Clark Kimberling_, Oct 22 2011