sin w=z
sin
w=((e^{iw}-e^{iw})/(2i))
e^{iw}-e^{-iw}=2iz multiply everything by
e^{iw}
e^{2iw}-1=2ize^{iw}
e^{2iw}-2ize^{iw}-1=0
y=e^{iw}
y²-2izy-1=0
y=((2iz±√((-2iz)²-4(-1)))/2)=((-iz±√(-4z²+4))/2)
e^{iw}=-iz±√(1-z²)
so our answer
is
iw=ln(-iz±√(1-z²))
w=(1/i)ln(-iz±√(1-z²))+2πn
I
do not see an easy way to solve this equation for z.
z=0 is
an obvious solution.
Using newton's method on the original
function
f(z) = sin(z)-z
f
'(z) = cos(z) - 1
Pick a x_0 and iterate the following
formula
x_(n+1) = x_n - f(x_n)/f
'(x_n)
I get z = 7.4976763 - 2.7686783 i as one posible
answer from about 10 iterations starting with (5+5i)
z =
13.899960 - 3.3522099 i is another answer.
I do not see a
pattern, but perhaps you can...
No comments:
Post a Comment