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A198229 Decimal expansion of greatest x having 3*x^2+2x=4*cos(x). 3

%I

%S 7,2,1,3,4,1,3,0,7,6,4,8,0,1,5,5,8,2,4,2,1,0,3,1,7,2,2,8,7,2,3,0,6,4,

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

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

%N Decimal expansion of greatest x having 3*x^2+2x=4*cos(x).

%C See A197737 for a guide to related sequences. The Mathematica program includes a graph.

%e least x: -1.146069580210441813394351195780611...

%e greatest x: 0.721341307648015582421031722872306448...

%t a = 3; b = 2; c = 4;

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

%t Plot[{f[x], g[x]}, {x, -2, 1}]

%t r1 = x /. FindRoot[f[x] == g[x], {x, -1.2, -1.1}, WorkingPrecision -> 110]

%t RealDigits[r1] (* A198228 *)

%t r2 = x /. FindRoot[f[x] == g[x], {x, .72, .73}, WorkingPrecision -> 110]

%t RealDigits[r2] (* A198229 *)

%Y Cf. A197737.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Oct 23 2011

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Last modified August 4 12:41 EDT 2020. Contains 336201 sequences. (Running on oeis4.)