Question

How to write mathematical equations using python? (after importing the module)

Answer 1

>>> import math
>>> math.sqrt(4)
>>> 2.0
>>> math.sqrt(4) * 3
>>> 6.0

Just import math then you can use any of the specialized math functions (like the square root function I used above). You can use basic math operators like multiplication, addition, modulus, etc without importing math. Take special care to ensure you're doing floating point math if you want a floating point result, (4/3 = 1 because 4 and 3 are integers, but 4.0/3.0 = 1.333... because 4.0 and 3.0 are floating point numbers).

You can find a list of all the math functions available here:
http://docs.python.org/release/2.5.4/lib/module-math.html