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

%I #9 Feb 19 2019 23:36:24

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

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

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

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

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

%H G. C. Greubel, <a href="/A199046/b199046.txt">Table of n, a(n) for n = 1..10000</a>

%e negative: -1.72846631899717722235659184827479...

%e positive: 1.06154977463138382560203340351989...

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

%t f[x_] := a*x^2 + b*Sin[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, -1.73, -1.72}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199046 *)

%t r = x /. FindRoot[f[x] == g[x], {x, 1.06, 1.07}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199047 *)

%o (PARI) a=1; b=1; c=0; solve(x=-2, 0, a*x^2 - c + b*sin(x)) \\ _G. C. Greubel_, Feb 19 2019

%o (Sage) a=1; b=1; c=2; (a*x^2 + b*sin(x)==c).find_root(-2,0,x) # _G. C. Greubel_, Feb 19 2019

%Y Cf. A198866.

%K nonn,cons

%O 1,2

%A _Clark Kimberling_, Nov 02 2011

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Last modified September 24 07:26 EDT 2024. Contains 376187 sequences. (Running on oeis4.)