In the beginning, you learnt how to add “one” to a number. Three becomes four, four becomes five, and so on. Then you’ve learnt addition, where you repeat adding 1s to a number.
One day, you learnt that you can repeatedly add a number, which you now know as multiplying:
\[a \times n = \underbrace{a+a+a+\dotsb+a}_{\text{\(n\) times}}\]
Can you repeat multiplication?
Sure! This is what this chapter’s about.