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A198138
Decimal expansion of least x having 3*x^2+4x=4*cos(x).
3
1, 4, 4, 7, 0, 5, 7, 1, 5, 1, 0, 4, 1, 6, 5, 5, 0, 7, 8, 7, 7, 9, 4, 7, 1, 6, 8, 1, 4, 4, 9, 8, 8, 0, 6, 2, 7, 5, 0, 5, 7, 7, 2, 9, 3, 2, 5, 5, 0, 6, 3, 6, 8, 9, 6, 4, 8, 9, 5, 3, 3, 6, 2, 9, 5, 4, 9, 4, 1, 3, 3, 4, 8, 1, 0, 8, 7, 4, 9, 3, 3, 3, 4, 4, 2, 9, 6, 6, 7, 5, 8, 2, 5, 8, 1, 5, 7, 7, 9
OFFSET
1,2
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -1.447057151041655078779471681449880627...
greatest x: 0.5817200797316597228428659232714882...
MATHEMATICA
a = 3; b = 4; 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, -1.5, -1.4}, WorkingPrecision -> 110]
RealDigits[r1] (* A198138 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .58, .59}, WorkingPrecision -> 110]
RealDigits[r2] (* A198139 *)
CROSSREFS
Cf. A197737.
Sequence in context: A090531 A350581 A356686 * A300709 A240924 A319034
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 23 2011
STATUS
approved