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A197845
Decimal expansion of least x having x^2+2x=3*cos(x).
3
1, 7, 2, 8, 0, 7, 8, 0, 8, 6, 2, 5, 3, 1, 4, 2, 1, 7, 1, 3, 9, 7, 2, 4, 5, 4, 3, 2, 4, 2, 4, 7, 6, 8, 2, 6, 7, 7, 6, 2, 0, 8, 0, 6, 2, 0, 8, 4, 3, 1, 3, 3, 5, 4, 1, 6, 2, 6, 1, 2, 4, 2, 5, 1, 3, 8, 6, 4, 1, 6, 9, 0, 4, 2, 6, 1, 7, 0, 0, 3, 8, 7, 3, 5, 0, 7, 3, 9, 8, 9, 6, 7, 6, 4, 8, 6, 2, 4, 4
OFFSET
1,2
COMMENTS
See A197737 for a guide to related sequences. The Mathematica program includes a graph.
EXAMPLE
least x: -1.72807808625314217139724543242476826...
greatest x: 0.773696189243809421714739053530453...
MATHEMATICA
a = 1; b = 2; c = 3;
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, -1.8, -1.7}, WorkingPrecision -> 110]
RealDigits[r1] (* A197845 *)
r2 = x /. FindRoot[f[x] == g[x], {x, .77, .78}, WorkingPrecision -> 110]
RealDigits[r2] (* A197846 *)
CROSSREFS
Cf. A197737.
Sequence in context: A248791 A253383 A010506 * A082633 A121239 A348362
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 20 2011
STATUS
approved