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A199612
Decimal expansion of greatest x satisfying x + 4*cos(x) = 0.
3
3, 5, 9, 5, 3, 0, 4, 8, 6, 7, 1, 6, 1, 5, 4, 7, 9, 9, 1, 8, 7, 7, 6, 0, 6, 9, 3, 5, 0, 8, 3, 4, 1, 8, 7, 1, 4, 9, 1, 3, 1, 1, 1, 4, 3, 7, 7, 7, 5, 5, 2, 9, 3, 2, 5, 1, 8, 5, 5, 2, 2, 4, 8, 6, 9, 1, 2, 8, 2, 5, 3, 0, 1, 8, 4, 3, 4, 6, 3, 7, 8, 9, 3, 9, 0, 9, 9, 1, 7, 5, 8, 2, 7, 7, 2, 2, 7, 7, 3
OFFSET
1,1
COMMENTS
See A199597 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least: -1.25235323400258876318632812197538043590128...
greatest: 3.595304867161547991877606935083418714913111...
MATHEMATICA
a = 1; b = 4; c = 0;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c*Sin[x]
Plot[{f[x], g[x]}, {x, -2, 4}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -1.3, -1.2}, WorkingPrecision -> 110]
RealDigits[r] (* A199611, least of 4 roots *)
r = x /. FindRoot[f[x] == g[x], {x, 3.5, 3.6}, WorkingPrecision -> 110]
RealDigits[r] (* A199612, greatest of 4 roots *)
CROSSREFS
Sequence in context: A189044 A299793 A356527 * A076844 A198558 A286566
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 08 2011
EXTENSIONS
a(86) onwards corrected by Georg Fischer, Aug 03 2021
STATUS
approved