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Question

I am trying to write a Python function called term_output that can evaluate what a single term equals at a value of x .

For example, when x=2 , the term 3x^2 = 3*2^2=12 . I've been told to represent 3x^2 in code as (3, 2), and: term_output((3, 2), 2) should return 12 .

I am trying to use solely functions (and functions of functions)

def term(x,y):
    return x**y

def term_output(term,z):
    return term*z

My end result is (3, 2, 3, 2) .

But I have tried many options and i expect the output to return 12

Answer 1

term is a pair, not a number, and multiplying any tuple duplicates it.

>>> (1,2) * 3
(1, 2, 1, 2, 1, 2)
>>> (1,2) * 4
(1, 2, 1, 2, 1, 2, 1, 2)

You need to take apart the pair.
I think simultaneous assignment is convenient (and it documents the intent better than indexing):

>>> a = (3,2)
>>> a
(3, 2)
>>> x,y = a
>>> x
3
>>> y
2

Putting it in a function:

def term_output(term,z):
    coefficent, exponent = term
    return coefficient * z ** exponent

Answer 2

Simply as:

x = 2
y = 2
z = 3
xy = [x,y]

def term(xy):
    return xy[0]**xy[1]

def term_output(xy,z):
    return term(xy)*z