Now it's time to say goodbye to that course about the natural integers.

What did we learn? We learned all the uses of natural integers, that are. A way to count efficiently from zero to infinity.

A way to compare quantities.

A way to manipulate quantities with the addition, the subtraction, the multiplication and the exponentiation.

And a way to compare the results of operations on numbers.

What else did we learn? We were introduced to computational mathematics.

Now we master the computation of literal expressions.

We can solve additive and subtractive equations and inequations.

We can draw straight lines in Python with a glance to sequences of numbers.

We may define and draw polynomials.

And we have opened our minds to the exponential growing.

What's next? The signed integers.

You will discover all the uses of integers of any signs.

That is a way to get an answer to any subtraction of integers.

a way to compare two results of a balance, A way to transform subtraction in addition of the opposite.

A way to extend multiplication and exponentiation easily with the sign rules.

A way to compare the results of additions, subtractions and multiplications.

So goodbye, the natural integers.

And hello, the signed integers!