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A197844
Decimal expansion of greatest x having x^2+2x=2*cos(x).
3
6, 2, 0, 7, 6, 2, 3, 3, 6, 5, 8, 6, 6, 1, 4, 7, 1, 4, 4, 5, 2, 1, 2, 0, 2, 4, 7, 3, 2, 1, 5, 1, 5, 3, 7, 1, 4, 4, 3, 4, 1, 1, 7, 7, 8, 5, 8, 7, 1, 4, 0, 9, 1, 6, 4, 2, 4, 8, 3, 0, 0, 9, 3, 7, 3, 1, 1, 0, 4, 9, 0, 2, 1, 6, 0, 2, 3, 6, 8, 0, 1, 5, 1, 6, 3, 7, 1, 7, 0, 3, 1, 1, 5, 2, 5, 5, 7, 6, 2
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -1.77323215749171672703899464197081641...
greatest x: 0.620762336586614714452120247321515...
MATHEMATICA
a = 1; b = 2; c = 2;
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, -1.8, -1.7}, WorkingPrecision -> 110]
RealDigits[r1] (* A197843 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .62, .63}, WorkingPrecision -> 110]
RealDigits[r2] (* A197844 *)
CROSSREFS
Cf. A197737.
Sequence in context: A295188 A248680 A021621 * A326825 A182639 A244135
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 20 2011
STATUS
approved