A198813 - OEIS

%I #5 Mar 30 2012 18:57:56

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

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

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

%N Decimal expansion of x>0 satisfying x^2+3*cos(x)=4.

%C See A198755 for a guide to related sequences.  The Mathematica program includes a graph.

%e x=2.5463907758028887768561727093936128950373...

%t a = 1; b = 3; c = 4;

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

%t Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]

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

%t RealDigits[r] (* A198813 *)

%Y Cf. A198755.

%K nonn,cons

%O 1,1

%A _Clark Kimberling_, Oct 30 2011