A199602 - OEIS

%I #5 Mar 30 2012 18:57:58

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

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

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

%N Decimal expansion of x>0 satisfying x^2+2*x*cos(x)=4*sin(x).

%C See A199597 for a guide to related sequences.  The Mathematica program includes a graph.

%e x=2.54009241804274736385079439399483437...

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

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

%t Plot[{f[x], g[x]}, {x, -Pi, Pi}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, 2.5, 2.6}, WorkingPrecision -> 110]

%t RealDigits[r]   (* A199602 *)

%Y Cf. A199597.

%K nonn,cons

%O 1,1

%A _Clark Kimberling_, Nov 08 2011