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A200123
Decimal expansion of greatest x satisfying 2*x^2 - 3*cos(x) = 2*sin(x).
3
1, 2, 1, 0, 3, 0, 1, 1, 0, 2, 1, 5, 6, 0, 5, 7, 8, 5, 9, 1, 9, 2, 8, 4, 4, 2, 4, 6, 7, 5, 9, 4, 3, 4, 7, 8, 0, 3, 8, 1, 4, 9, 4, 7, 5, 5, 4, 4, 3, 5, 2, 6, 5, 4, 1, 2, 5, 5, 9, 4, 7, 5, 6, 4, 0, 2, 5, 1, 2, 6, 1, 3, 0, 6, 7, 4, 9, 2, 0, 3, 2, 8, 7, 4, 6, 6, 2, 1, 4, 2, 7, 4, 1, 2, 6, 4, 8, 3, 5
OFFSET
1,2
COMMENTS
See A199949 for a guide to related sequences. The Mathematica program includes a graph.
LINKS
EXAMPLE
least x: -0.70415945703712255268105833349948348210...
greatest x: 1.210301102156057859192844246759434780...
MATHEMATICA
a = 2; b = -3; c = 2;
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, -.71, -.70}, WorkingPrecision -> 110]
RealDigits[r] (* A200122 *)
r = x /. FindRoot[f[x] == g[x], {x, 1.2, 1.3}, WorkingPrecision -> 110]
RealDigits[r] (* A200123 *)
PROG
(PARI) a=2; b=-3; c=2; solve(x=1, 2, a*x^2 + b*cos(x) - c*sin(x)) \\ G. C. Greubel, Jun 29 2018
CROSSREFS
Cf. A199949.
Sequence in context: A165252 A371954 A127373 * A187616 A217262 A378148
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Nov 14 2011
STATUS
approved