# Chapter 5 Equation Models Review

Next is chapter 5. Chapter 5 was pretty laden as well. Chapter 5 has cubic functions. Chapter 5 has polynomial functions. [student coughs] And by the way, that is section 5.1 and 5.2. And 5.3 which is today’s lesson; is rational functions. Cubic functions are y equals a x cubed,
plus b x squared, plus c x, plus d. Regression comes into play. y sub 1, tilde, a x sub 1, 3, plus b x sub 1, 2, plus c x sub 1, plus d. Oh, I see one we forgot. Okay. Polynomial functions. They are all of those that extend this. So they are
things like the quartic, the fifth power, the sixth power. Okay, so those are
the polynomials can go on from there. We also have one in here that I almost
forgot. Power functions. That’s also hidden in there. The power functions have
a y equals a x to the b power. Power functions gives you a hint that it
has something to do with an exponent. Power functions can have regression as well. y sub 1, tilde, a x sub 1, raised to the b power. Rational functions. We’re going to cover
today.