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

%I #6 Mar 30 2012 18:57:53

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

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

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

%N Decimal expansion of least x having 2*x^2-3x=-cos(x).

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

%e least x: 0.42341886743695639025490191456713...

%e greatest x: 1.46336282729643114510529642616...

%t a = 2; b = -3; c = -1;

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

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

%t r1 = x /. FindRoot[f[x] == g[x], {x, -.43, -.42}, WorkingPrecision -> 110]

%t RealDigits[r1](* A198120 *)

%t r2 = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]

%t RealDigits[r2](* A198121 *)

%Y Cf. A197737.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Oct 21 2011