Funzioni e medie

def media2(x, y):     return (x+y)/2
def media3(x, y, z):  return (x+y+z)/3

a=18
b=19
c=28

... media2(a, b)     # 18.5
... media2(a, c)     # 23.0
... media2(b, c)     # 23.5
... media3(a, b, c)  # 21.67

import math

def media2g(x, y):    return math.sqrt(x*y)
def media3g(x, y, z): return math.pow(x*y*z, 1/3)

a=18
b=19
c=28

... media2g(a, b)    # 18.49 
... media2g(a, c)    # 22.45 
... media2g(b, c)    # 23.065 
... media3g(a, b, c) # 21.235