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 A197839 Decimal expansion of least x having x^2-4x=-cos(x). 3

%I

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

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

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

%N Decimal expansion of least x having x^2-4x=-cos(x).

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

%e least x: 0.25839214437159967402757423807386027526101...

%e greatest x: 4.13257347075386830819844170536280612105...

%t a = 1; b = -4; c = -1;

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

%t Plot[{f[x], g[x]}, {x, -1, 5}]

%t r1 = x /. FindRoot[f[x] == g[x], {x, -4.2, -4.1}, WorkingPrecision -> 110]

%t RealDigits[r1] (* A197839 *)

%t r2 = x /. FindRoot[f[x] == g[x], {x, 4.1, 4.2}, WorkingPrecision -> 110]

%t RealDigits[r2] (* A197840 *)

%Y Cf. A197737.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Oct 20 2011

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Last modified December 15 22:02 EST 2019. Contains 330012 sequences. (Running on oeis4.)