A198993 - OEIS

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

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

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

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

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

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

%e x=1.008292167888835471427809853991686647334378423...

%t a = 4; b = -2; c = 3;

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

%t Plot[{f[x], g[x]}, {x, -2, 2}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, 1, 1.01}, WorkingPrecision -> 110]

%t RealDigits[r] (* A198993 *)

%Y Cf. A198755.

%K nonn,cons

%O 1,4

%A _Clark Kimberling_, Nov 01 2011