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A198221
Decimal expansion of greatest x having 3*x^2+x=4*cos(x).
3
8, 0, 7, 6, 7, 8, 4, 8, 2, 4, 2, 7, 2, 1, 0, 6, 5, 0, 9, 1, 8, 0, 5, 7, 2, 1, 3, 0, 7, 8, 3, 7, 5, 6, 6, 3, 5, 0, 3, 8, 6, 6, 3, 6, 1, 6, 6, 1, 1, 3, 0, 6, 4, 0, 9, 0, 6, 6, 7, 9, 8, 0, 4, 1, 2, 7, 9, 3, 8, 4, 5, 9, 3, 1, 7, 3, 4, 2, 5, 1, 7, 7, 5, 5, 3, 8, 9, 7, 0, 5, 9, 1, 5, 1, 4, 1, 2, 1, 4
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -1.0190925028154180679841791260898590369...
greatest x: 0.807678482427210650918057213078375663...
MATHEMATICA
a = 3; b = 1; c = 4;
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, -1.1, -1}, WorkingPrecision -> 110]
RealDigits[r1] (* A198220 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .8, .9}, WorkingPrecision -> 110]
RealDigits[r2] (* A198221 *)
CROSSREFS
Cf. A197737.
Sequence in context: A306071 A201321 A245737 * A183001 A262522 A174849
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 22 2011
STATUS
approved