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A198357
Decimal expansion of least x having 4*x^2+2x=cos(x).
3
7, 4, 6, 0, 7, 4, 3, 6, 2, 1, 2, 8, 5, 6, 4, 4, 6, 1, 7, 3, 2, 5, 7, 4, 1, 8, 9, 8, 5, 6, 5, 3, 0, 6, 7, 3, 5, 6, 8, 5, 1, 9, 0, 1, 4, 6, 8, 5, 0, 2, 7, 8, 5, 6, 9, 0, 8, 2, 2, 9, 6, 4, 8, 7, 6, 6, 2, 2, 9, 3, 3, 0, 9, 6, 2, 0, 1, 6, 5, 1, 3, 7, 8, 3, 6, 3, 0, 2, 6, 7, 3, 7, 8, 0, 4, 5, 1, 1, 2
OFFSET
0,1
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -0.7460743621285644617325741898565306735...
greatest x: 0.29900587455031735703746835072454193932...
MATHEMATICA
a = 4; 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, -.8, -.7}, WorkingPrecision -> 110]
RealDigits[r1] (* A198357 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .29, .30}, WorkingPrecision -> 110]
RealDigits[r2] (* A198358 *)
CROSSREFS
Cf. A197737.
Sequence in context: A085662 A155684 A345292 * A371850 A240341 A011204
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 24 2011
STATUS
approved