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A198109
Decimal expansion of greatest x having x^2+3x=4*cos(x).
3
7, 6, 5, 7, 2, 6, 4, 4, 2, 9, 2, 0, 5, 4, 0, 7, 1, 7, 4, 8, 3, 1, 0, 1, 0, 4, 9, 2, 3, 9, 4, 4, 9, 9, 3, 8, 2, 5, 9, 3, 8, 8, 0, 0, 4, 2, 0, 4, 9, 6, 3, 7, 0, 7, 0, 8, 5, 2, 1, 5, 1, 7, 2, 8, 8, 4, 5, 8, 6, 9, 4, 9, 7, 5, 8, 1, 7, 4, 9, 7, 9, 4, 2, 2, 8, 3, 9, 2, 5, 1, 1, 7, 8, 8, 9, 2, 8, 8, 8
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -2.072191302711809327379682290027003...
greatest x: 0.7657264429205407174831010492394...
MATHEMATICA
a = 1; b = 3; c = 4;
f[x_] := a*x^2 + b*x; g[x_] := c*Cos[x]
Plot[{f[x], g[x]}, {x, -3, 1}]
r1 = x /. FindRoot[f[x] == g[x], {x, -2.1, -2.9}, WorkingPrecision -> 110]
RealDigits[r1] (* A198108 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .76, .77}, WorkingPrecision -> 110]
RealDigits[r2] (* A198109 *)
CROSSREFS
Cf. A197737.
Sequence in context: A104178 A092874 A371322 * A059751 A019859 A188736
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 21 2011
STATUS
approved