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Decimal expansion of x>0 having x^2-4x=2*sin(x).
2

%I #5 Mar 30 2012 18:57:54

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

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

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

%N Decimal expansion of x>0 having x^2-4x=2*sin(x).

%C See A198414 for a guide to related sequences. The Mathematica program includes a graph.

%e x=3.70986661006749719419447510145732666...

%t a = 1; b = -4; c = 2;

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

%t Plot[{f[x], g[x]}, {x, -.2, 4}]

%t r = x /. FindRoot[f[x] == g[x], {x, 3.7, 3.71}, WorkingPrecision -> 110]

%t RealDigits[r] (* A198490 *)

%Y Cf. A198414.

%K nonn,cons

%O 1,1

%A _Clark Kimberling_, Oct 25 2011