gvitalie

me@amadeus:~$ python3 -q
>>> 
>>> import cmath
>>> 
>>> a = 3
>>> for i in range(3):
...     a -= cmath.exp(a * 1j).imag/cmath.exp(a * 1j).real
... 
>>> 
>>> print(a)

gvitalie

me@amadeus:~$ python3 -q
>>> 
>>> import cmath
>>> 
>>> a = 3
>>> for i in range(3):
...     a += cmath.exp(a * 1j).imag
... 
>>> print(a)
3.141592653589793

gvitalie

import math

def sin(x):
    a = 0
    for i in range(30):
        a += ((-1) ** i) * (x ** (2*i+1)) / math.factorial(2*i+1)
    return a

a = 3
for i in range(3):

gvitalie

me@amadeus:~$ python3 -q
>>> 
>>> from math import sin
>>> 
>>> a = 3
>>> for i in range(3):
...     a += sin(a)
... 
>>> print(a)
3.141592653589793