login
The OEIS Foundation is supported by donations from users of the OEIS and by a grant from the Simons Foundation.

 

Logo


Hints
(Greetings from The On-Line Encyclopedia of Integer Sequences!)
A199173 Decimal expansion of x>0 satisfying x^2+x*cos(x)=2. 3

%I

%S 1,2,7,6,6,7,1,3,6,7,9,4,0,7,6,0,5,5,4,0,9,1,5,0,7,4,9,0,4,4,1,2,1,0,

%T 2,7,8,3,4,0,0,2,4,6,4,7,3,4,5,6,7,6,0,6,1,5,6,6,2,8,7,6,7,4,1,2,5,9,

%U 6,3,2,8,0,1,0,9,7,6,3,1,1,9,2,3,4,4,1,8,2,9,4,3,2,4,2,4,5,7,8

%N Decimal expansion of x>0 satisfying x^2+x*cos(x)=2.

%C See A199170 for a guide to related sequences. The Mathematica program includes a graph.

%e negative: -1.4669783053971235684198141847804443...

%e positive: 1.27667136794076055409150749044121027834...

%t a = 1; b = 1; c = 2;

%t f[x_] := a*x^2 + b*x*Cos[x]; g[x_] := c

%t Plot[{f[x], g[x]}, {x, -2 Pi, 2 Pi}, {AxesOrigin -> {0, 0}}]

%t r = x /. FindRoot[f[x] == g[x], {x, -1.5, -1.3}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199172 *)

%t r = x /. FindRoot[f[x] == g[x], {x, 1.27, .28}, WorkingPrecision -> 110]

%t RealDigits[r] (* A199173 *)

%Y Cf. A199170.

%K nonn,cons

%O 1,2

%A _Clark Kimberling_, Nov 04 2011

Lookup | Welcome | Wiki | Register | Music | Plot 2 | Demos | Index | Browse | More | WebCam
Contribute new seq. or comment | Format | Style Sheet | Transforms | Superseeker | Recent
The OEIS Community | Maintained by The OEIS Foundation Inc.

License Agreements, Terms of Use, Privacy Policy. .

Last modified February 25 18:40 EST 2020. Contains 332256 sequences. (Running on oeis4.)