OFFSET
1,3
COMMENTS
See the Mathematica program for a graph.
xo=0.3695425666075803208276560438369...
yo=0.4039727532995172093189617400663...
m=1.09316974498501692208815321416057...
|OP|=0.54749949218543621432520415035...
FORMULA
Equals sqrt(2-2*sqrt(1-d^2))/d where d = A003957. - Gleb Koloskov, Jun 16 2021
MATHEMATICA
c = Pi/4;
xo = x /. FindRoot[x == Sin[x + c] Cos[x + c], {x, .8, 1.2}, WorkingPrecision -> 100]
RealDigits[xo] (* A197002 *)
m = 1/Sin[xo + c]
RealDigits[m] (* A197003 *)
yo = m*xo
d = Sqrt[xo^2 + yo^2]
Show[Plot[{Cos[x + c], yo - (1/m) (x - xo)}, {x, -Pi/4, 1}], ContourPlot[{y == m*x}, {x, 0, Pi}, {y, 0, 1}], PlotRange -> All, AspectRatio -> Automatic, AxesOrigin -> Automatic]
PROG
(PARI) my(d=solve(x=0, 1, cos(x)-x)); sqrt(2-2*sqrt(1-d^2))/d \\ Gleb Koloskov, Jun 16 2021
CROSSREFS
KEYWORD
nonn,cons
AUTHOR
Clark Kimberling, Oct 09 2011
STATUS
approved