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A200133
Decimal expansion of greatest x satisfying 3*x^2 - cos(x) = sin(x).
3
6, 8, 4, 8, 5, 3, 0, 7, 8, 6, 2, 3, 2, 0, 1, 1, 5, 9, 5, 6, 3, 6, 9, 4, 4, 6, 8, 6, 4, 9, 5, 4, 2, 8, 8, 8, 4, 5, 1, 8, 4, 2, 6, 1, 0, 3, 1, 8, 2, 0, 2, 6, 7, 1, 9, 2, 8, 2, 6, 1, 9, 9, 7, 6, 4, 6, 0, 2, 2, 5, 8, 4, 0, 3, 1, 2, 9, 4, 4, 3, 2, 7, 9, 2, 2, 5, 9, 2, 5, 2, 4, 0, 4, 6, 8, 1, 0, 2, 3
OFFSET
0,1
COMMENTS
See A199949 for a guide to related sequences. The Mathematica program includes a graph.
LINKS
EXAMPLE
least x: -0.4137517591447739376844002798989...
greatest x: 0.684853078623201159563694468649...
MATHEMATICA
a = 3; b = -1; c = 1;
f[x_] := a*x^2 + b*Cos[x]; g[x_] := c*Sin[x]
Plot[{f[x], g[x]}, {x, -3, 3}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, -.42, -.41}, WorkingPrecision -> 110]
RealDigits[r] (* A200132 *)
r = x /. FindRoot[f[x] == g[x], {x, .68, .69}, WorkingPrecision -> 110]
RealDigits[r] (* A200133 *)
PROG
(PARI) a=3; b=-1; c=1; solve(x=0, 1, a*x^2 + b*cos(x) - c*sin(x)) \\ G. C. Greubel, Jul 05 2018
CROSSREFS
Cf. A199949.
Sequence in context: A269802 A269991 A171784 * A021150 A347407 A065166
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 14 2011
STATUS
approved