What is a function
Alternative videos to explain what is a function ?
What is a Function?
https://youtu.be/22A4KMU7-uo (3m59s)
Meat-A-Morphosis: An Introduction to Functions
https://youtu.be/VUTXsPFx-qQ (7m45s)
Algebra Basics: What Are Functions? - Math Antics
https://youtu.be/52tpYl2tTqk (11m33s)
See an alternative function machine that processes patterns, numbers and simple equations.
https://phet.colorado.edu/sims/html/function-builder/latest/function-builder_en.html