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A198116
Decimal expansion of least x having 2*x^2+x=3*cos(x).
3
1, 1, 0, 6, 6, 9, 5, 8, 9, 2, 8, 6, 3, 5, 0, 3, 1, 2, 3, 6, 0, 5, 9, 4, 5, 6, 7, 5, 9, 2, 0, 8, 2, 0, 8, 0, 2, 3, 1, 2, 9, 0, 8, 0, 2, 1, 7, 5, 4, 9, 9, 6, 7, 8, 5, 5, 3, 0, 1, 5, 2, 5, 0, 9, 8, 6, 6, 6, 8, 0, 9, 5, 3, 5, 3, 2, 9, 3, 1, 6, 5, 5, 2, 8, 1, 8, 1, 9, 3, 3, 2, 0, 6, 8, 3, 5, 1, 4, 0
OFFSET
1,4
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -1.1066958928635031236059456759208208...
greatest x: 0.80159198729974720435776444320005779...
MATHEMATICA
a = 2; b = 1; c = 3;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -2, 1}]
r1 = x /. FindRoot[f[x] == g[x], {x, -1.2, -1.1}, WorkingPrecision -> 110]
RealDigits[r1] (* A198116 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .8, .9}, WorkingPrecision -> 110]
RealDigits[r2](* A198117 *)
CROSSREFS
Cf. A197737.
Sequence in context: A021603 A250721 A065480 * A200023 A339705 A337607
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 21 2011
STATUS
approved