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A199178
Decimal expansion of x < 0 satisfying x^2 + 2*x*cos(x) = 2.
3
1, 4, 9, 3, 5, 1, 9, 2, 8, 0, 8, 6, 8, 8, 9, 1, 0, 5, 6, 5, 5, 6, 3, 3, 9, 5, 0, 9, 9, 3, 4, 7, 8, 1, 8, 2, 5, 3, 5, 5, 3, 8, 1, 3, 0, 7, 4, 1, 8, 8, 4, 7, 6, 4, 8, 1, 6, 4, 1, 8, 0, 2, 9, 9, 2, 7, 6, 3, 4, 0, 0, 6, 0, 8, 5, 8, 4, 0, 4, 0, 8, 6, 5, 1, 5, 6, 3, 5, 2, 0, 3, 0, 4, 0, 4, 1, 8, 6, 2
OFFSET
1,2
COMMENTS
See A199170 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
negative: -1.49351928086889105655633950993478182...
positive: 0.94494832910354696494592764037834555...
MATHEMATICA
a = 1; b = 2; c = 2;
f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c
Plot[{f[x], g[x]}, {x, -5, 3}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -1.5, -1.4}, WorkingPrecision -> 110]
RealDigits[r] (* A199178 *)
r = x /. FindRoot[f[x] == g[x], {x, .2, .53}, WorkingPrecision -> 110]
RealDigits[r] (* A199179 *)
CROSSREFS
Sequence in context: A159628 A102753 A200416 * A318331 A198828 A200369
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 04 2011
EXTENSIONS
a(91) onwards corrected by Georg Fischer, Aug 03 2021
STATUS
approved