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A199182
Decimal expansion of least x satisfying x^2+3*x*cos(x)=1.
4
1, 3, 6, 0, 6, 7, 2, 7, 7, 2, 5, 1, 3, 7, 9, 7, 2, 1, 5, 2, 2, 8, 6, 0, 2, 7, 4, 8, 7, 3, 7, 9, 9, 2, 5, 8, 8, 0, 9, 6, 8, 6, 2, 8, 0, 8, 5, 7, 6, 1, 8, 0, 9, 4, 7, 4, 5, 8, 1, 9, 1, 7, 7, 1, 9, 7, 1, 2, 0, 7, 6, 2, 0, 8, 6, 5, 3, 3, 7, 9, 2, 3, 5, 3, 1, 4, 1, 9, 0, 8, 0, 8, 3, 3, 8, 2, 9, 4, 0
OFFSET
1,2
COMMENTS
See A199170 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least: -1.3606727725137972152286027487379925...
greatest: 3.27746466341373058734587727791083...
MATHEMATICA
a = 1; b = 3; c = 1;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c
Plot[{f[x], g[x]}, {x, -2 Pi, 2 Pi}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -1.4, -1.3}, WorkingPrecision -> 110]
RealDigits[r] (* A199182 least of four roots *)
r = x /. FindRoot[f[x] == g[x], {x, 3.27, 3.28}, WorkingPrecision -> 110]
RealDigits[r] (* A199183 greatest of four roots *)
CROSSREFS
Cf. A199170.
Sequence in context: A359295 A181916 A077590 * A011368 A020811 A200005
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 04 2011
STATUS
approved