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A198217
Decimal expansion of greatest x having 3*x^2+x=2*cos(x).
3
5, 9, 4, 8, 6, 3, 2, 8, 0, 3, 5, 7, 7, 1, 8, 7, 1, 4, 1, 7, 1, 5, 9, 2, 0, 7, 7, 9, 0, 1, 0, 2, 7, 8, 7, 9, 8, 5, 8, 9, 2, 3, 1, 4, 3, 6, 2, 3, 3, 0, 7, 1, 6, 5, 9, 4, 0, 1, 0, 4, 6, 0, 3, 6, 1, 2, 2, 2, 0, 2, 3, 7, 9, 1, 3, 1, 2, 7, 6, 0, 4, 4, 5, 2, 2, 4, 8, 4, 5, 7, 6, 4, 2, 3, 6, 0, 8, 3, 8
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -0.850440081427008538547913177891557825...
greatest x: 0.59486328035771871417159207790102787...
MATHEMATICA
a = 3; b = 1; c = 2;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -1, 1}]
r1 = x /. FindRoot[f[x] == g[x], {x, -.9, -.8}, WorkingPrecision -> 110]
RealDigits[r1] (* A198216 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .59, .6}, WorkingPrecision -> 110]
RealDigits[r2] (* A198217 *)
CROSSREFS
Cf. A197737.
Sequence in context: A340216 A198748 A196754 * A021631 A376009 A201325
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 22 2011
STATUS
approved