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A200005
Decimal expansion of greatest x satisfying 2*x^2 + cos(x) = 4*sin(x).
3
1, 3, 6, 0, 8, 3, 2, 2, 5, 5, 3, 9, 0, 6, 6, 8, 9, 0, 4, 6, 7, 1, 8, 3, 9, 2, 8, 5, 6, 9, 1, 3, 2, 6, 3, 6, 8, 8, 2, 5, 4, 9, 7, 9, 2, 6, 2, 5, 5, 0, 8, 5, 8, 3, 1, 1, 0, 7, 4, 1, 3, 2, 6, 7, 8, 2, 0, 6, 1, 0, 6, 2, 3, 0, 1, 3, 9, 9, 4, 2, 4, 7, 4, 6, 2, 9, 0, 5, 6, 4, 0, 9, 9, 1, 4, 8, 2, 9, 9
OFFSET
1,2
COMMENTS
See A199949 for a guide to related sequences. The Mathematica program includes a graph.
LINKS
EXAMPLE
least x: 0.2841554251771481491680536288735443310...
greatest x: 1.36083225539066890467183928569132636...
MATHEMATICA
a = 2; b = 1; c = 4;
f[x_] := a*x^2 + b*Cos[x]; g[x_] := c*Sin[x]
Plot[{f[x], g[x]}, {x, -.1, 2}, {AxesOrigin -> {0, 0}}]
r = x /. FindRoot[f[x] == g[x], {x, .28, .29}, WorkingPrecision -> 110]
RealDigits[r] (* A200004 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.3, 1.4}, WorkingPrecision -> 110]
RealDigits[r] (* A200005 *)
PROG
(PARI) a=2; b=1; c=4; solve(x=1, 2, a*x^2 + b*cos(x) - c*sin(x)) \\ G. C. Greubel, Jun 23 2018
CROSSREFS
Cf. A199949.
Sequence in context: A199182 A011368 A020811 * A153097 A271854 A077086
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 12 2011
STATUS
approved