A199471 - OEIS

%I #7 Mar 30 2012 18:57:57

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

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

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

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

%C See A199429 for a guide to related sequences.  The Mathematica program includes a graph.

%e x=0.796430416796343079696359002296588118021270...

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

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

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

%t r = x /. FindRoot[f[x] == g[x], {x, .79, .80}, WorkingPrecision -> 110]

%t RealDigits[r]  (* A199471 *)

%Y Cf. A199429.

%K nonn,cons

%O 0,1

%A _Clark Kimberling_, Nov 07 2011