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Decimal expansion of x<0 satisfying x^2+3*sin(x)=2.
3

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

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

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

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

%N Decimal expansion of x<0 satisfying x^2+3*sin(x)=2.

%C See A198866 for a guide to related sequences. The Mathematica program includes a graph.

%e negative: -2.131047764056355710001133695358553...

%e positive: 0.58532056434199307654267468696737728...

%t a = 1; b = 3; c = 2;

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

%t Plot[{f[x], g[x]}, {x, -3, 2}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, -2.2, -2.1}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199056 *)

%t r = x /. FindRoot[f[x] == g[x], {x, .58, .59}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199057 *)

%Y Cf. A198866.

%K nonn,cons

%O 1,1

%A _Clark Kimberling_, Nov 02 2011