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A198127
Decimal expansion of greatest x having 2*x^2+2x=3*cos(x).
3
6, 8, 7, 2, 2, 8, 2, 9, 2, 2, 5, 2, 5, 4, 8, 8, 5, 4, 0, 1, 5, 3, 6, 6, 7, 6, 6, 9, 9, 7, 6, 1, 9, 0, 5, 2, 1, 7, 1, 1, 1, 6, 2, 1, 1, 9, 2, 3, 5, 6, 6, 2, 5, 0, 8, 5, 0, 8, 0, 1, 0, 4, 6, 0, 3, 6, 6, 6, 7, 9, 0, 0, 1, 1, 4, 7, 5, 2, 4, 3, 9, 0, 6, 9, 9, 0, 9, 2, 7, 7, 9, 3, 6, 1, 8, 3, 3, 8, 1
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -1.303688236082731236157942349201731581...
greatest x: 0.68722829225254885401536676699761905...
MATHEMATICA
a = 2; b = 2; 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, -1.31, -1.30}, WorkingPrecision -> 110]
RealDigits[r1] (* A198126 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .68, .69}, WorkingPrecision -> 110]
RealDigits[r2] (* A198127 *)
CROSSREFS
Cf. A197737.
Sequence in context: A141793 A283086 A283182 * A092294 A097668 A133748
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 22 2011
STATUS
approved