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Decimal expansion of least x>0 satisfying 3*x^2+4*x+1=tan(x).
2

%I #5 Mar 30 2012 18:58:00

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

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

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

%N Decimal expansion of least x>0 satisfying 3*x^2+4*x+1=tan(x).

%C See A200338 for a guide to related sequences. The Mathematica program includes a graph.

%e x=1.498064291275659004588361096015654898281433527...

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

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

%t Plot[{f[x], g[x]}, {x, -.1, Pi/2}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, 1.4, 1.5}, WorkingPrecision -> 110]

%t RealDigits[r] (* A200398 *)

%Y Cf. A200338.

%K nonn,cons

%O 1,2

%A _Clark Kimberling_, Nov 17 2011