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A198222
Decimal expansion of least x having 3*x^2+2x=cos(x), negated.
3
8, 9, 7, 9, 9, 1, 2, 1, 7, 8, 1, 5, 7, 7, 3, 7, 2, 3, 2, 7, 0, 9, 4, 3, 4, 7, 4, 5, 5, 1, 2, 3, 8, 3, 2, 2, 3, 4, 4, 2, 6, 5, 1, 2, 3, 7, 9, 3, 4, 8, 0, 7, 1, 3, 1, 4, 1, 5, 1, 3, 4, 7, 0, 8, 1, 2, 5, 4, 3, 5, 5, 9, 8, 9, 3, 2, 4, 5, 5, 8, 5, 1, 9, 4, 4, 4, 4, 2, 6, 7, 2, 5, 8, 4, 4, 1, 4, 4, 5, 7
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -0.8979912178157737232709434745512383...
greatest x: 0.320480477969135711421623476182676393...
MATHEMATICA
a = 3; b = 2; c = 1;
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] (* A198222 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .3, .4}, WorkingPrecision -> 110]
RealDigits[r2] (* A198223 *)
PROG
(PARI) solve(x=0, 1, 3*x^2-2*x-cos(x)) \\ Charles R Greathouse IV, Apr 10 2026
CROSSREFS
Cf. A197737.
Sequence in context: A019601 A337669 A379889 * A154582 A020507 A195341
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 22 2011
STATUS
approved