# Unit 4 – Logarithmic Functions

## Introduction

What is a logarithm? The answer is more simple than meets the eye. Essentially, a logarithm is the “backwards” version of an exponent and we will explore it that way. For many reasons we’ll discuss on class, there is a variety of connections between logarithms and exponential functions. Find some helpful videos below to build meaning around what a logarithm is, the properties it holds and how to use them to solve exponent problems.

## Standards

 F.BF.B.4 Find the inverse functions. F.BF.B.5 Understand the inverse relationship between exponents and logarithms and use this relationship to solve problem involving logarithms and exponents. F.IF.C.7.e Graph exponential and logarithmic functions, showing intercepts and end behavior. F.LE.A.4 For exponential models, express as a logarithm the solution to abct= d where a,c, and d are numbers and the base b is 2, 10 or e; evaluate the logarithm using technology. F.BF.B.3 Identify the effect on the graph of replacing f(x) by f(x) + k, k f(x), f(kx), and f(x+k) for specific values of k (both positive and negative); find the value of k given the graphs.  Experiment with cases and illustrate an explanation of the effects on the graph using technology.  Include recognizing even and odd function from their graphs and algebraic expressions for them.