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Decimal expansion of the greater of two values of x satisfying 5*x^2 - 4 = tan(x) and 0 < x < Pi/2.
3

%I #8 Apr 09 2021 15:50:52

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

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

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

%N Decimal expansion of the greater of two values of x satisfying 5*x^2 - 4 = tan(x) and 0 < x < Pi/2.

%C See A200614 for a guide to related sequences. The Mathematica program includes a graph.

%e lesser: 1.0862483073723514930516537470257901302111...

%e greater: 1.4001025553369417418319593715715854730538...

%t a = 5; c = 4;

%t f[x_] := a*x^2 - 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, .9, 1.0}, WorkingPrecision -> 110]

%t RealDigits[r] (* A200626 *)

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

%t RealDigits[r] (* A200627 *)

%Y Cf. A200614.

%K nonn,cons

%O 1,2

%A _Clark Kimberling_, Nov 20 2011