A198820 - OEIS

%I #7 Aug 09 2021 07:46:44

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

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

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

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

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

%e x=0.8093245699460672085363297141907319059600...

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

%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, .8, .81}, WorkingPrecision -> 110]

%t RealDigits[r] (* A198820 *)

%Y Cf. A198755.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Oct 31 2011