Evaluating Logarithms

Slides:



Advertisements
Similar presentations
Math Keeper 27 Logarithms
Advertisements

Essential Question: What are some of the similarities and differences between natural and common logarithms.
Logs and Exp as inverses
8.4 Logarithms p. 486.
WARM - UP. SOLVING EXPONENTIAL & LOGARITHMIC FUNCTIONS SECTION 3.4.
Copyright © Cengage Learning. All rights reserved.
Section 8.4 Logarithmic Functions Evaluate logarithmic functions Graph logarithmic functions.
6. 3 Logarithmic Functions Objectives: Write equivalent forms for exponential and logarithmic equations. Use the definitions of exponential and logarithmic.
LOGS EQUAL THE The inverse of an exponential function is a logarithmic function. Logarithmic Function x = log a y read: “x equals log base a of y”
Logarithmic Functions
Solve each equation for x. 1. 3x – 12 = 45 x = x = 39.2 Algebra 3 Warm-Up 5.3.
Objectives Use properties to simplify logarithmic expressions.
6.3A – Logarithms and Logarithmic Functions Objective: TSW evaluate logarithmic expressions.
6. 3 Logarithmic Functions Objectives: Write equivalent forms for exponential and logarithmic equations. Use the definitions of exponential and logarithmic.
Section 9.6 There are two logarithmic bases that occur so frequently in applications that they are given special names. Common logarithms are logarithms.
Skill 15: Converting Between Exponential and Logarithmic Forms Have SAT Practice Set 3 out on your desk.
Section 9.3 Logarithmic Functions  Graphs of Logarithmic Functions Log 2 x  Equivalent Equations  Solving Certain Logarithmic Equations 9.31.
Logarithmic Functions & Their Graphs
8-6 Natural Logarithms p. 462 Obj: To be able to solve equations using natural logarithms.
5.3 Intro to Logarithms 2/27/2013. Definition of a Logarithmic Function For y > 0 and b > 0, b ≠ 1, log b y = x if and only if b x = y Note: Logarithmic.
7.4 Logarithmic Functions Write equivalent forms for exponential and logarithmic equations. Use the definitions of exponential and logarithmic functions.
Trash-ket Ball Chapter 7 Exponents and Logarithms.
5.5Logarithms. Objectives: I will be able to…  Rewrite equations between exponential and logarithmic forms  Evaluate logarithms  Solve logarithms Vocabulary:
Holt McDougal Algebra Properties of Logarithms Warm Up 2. (3 –2 )(3 5 ) 1. (2 6 )(2 8 ) (7 3 ) 5 Simplify. Write in exponential form. 6.
8.3 – Logarithmic Functions and Inverses. What is a logarithm? A logarithm is the power to which a number must be raised in order to get some other number.
7.3 Logarithmic Functions as Inverses Objective(s): To write and evaluate logarithmic expressions To graph logarithmic functions.
Solving Logarithmic Equations I.. Relationship between Exponential and Logarithmic Equations. A) Logs and Exponentials are INVERSES of each other. 1) That.
Precalculus Section 5.5 Define and apply logarithms
8.4 Logarithmic Functions 4/8/2013. Definition of a Logarithmic Function log b n = p is equivalent to b p = n (logarithmic form) (exponential form)
Goals:  Understand logarithms as the inverse of exponents  Convert between exponential and logarithmic forms  Evaluate logarithmic functions.
Review of Logarithms. Review of Inverse Functions Find the inverse function of f(x) = 3x – 4. Find the inverse function of f(x) = (x – 3) Steps.
Logarithmic Functions & Their Graphs Goals— Recognize and evaluate logarithmic functions with base a Graph Logarithmic functions Recognize, evaluate, and.
Logarithmic Functions
5.2 Logarithmic Functions & Their Graphs
Aim: What is the logarithms?
10.2 Logarithms & Logarithmic Functions
6.1 - Logarithmic Functions
Solving Exponential and Logarithmic Equations
Solving Exponential Equations
Solving Logarithmic Equations
Warm Up WARM UP Evaluate the expression without using a calculator.
6. 3 Logarithmic Functions Objectives: Write equivalent forms for exponential and logarithmic equations. Use the definitions of exponential and logarithmic.
5 x2 + 4x = Warm-Up Evaluate the compositions if:
Lesson 6.3 Logartithms and Logarithmic Functions(Day 1)
Logarithmic Functions and Their Graphs
Solving Logarithmic Equations
Do Now: Determine the value of x in the expression.
Solving Exponential Equations
5.4 Logarithmic Functions and Models
Logarithmic Functions 3.2.
Logarithms and Logarithmic Functions
Logarithmic Functions
1. Find the inverse of the function y = 3x – 5.
Introduction to Logarithms
8.6 Solving Exponential and Logarithmic Equations
Warm Up Which plan yields the most interest? Invest $100 Plan A: A 7.5% annual rate compounded monthly for 4 years Plan B: A 7.2% annual rate compounded.
Solving Exponential & logarithmic Equations
5A.1 - Logarithmic Functions
More Logarithms Graphing and Inverses
8.3 – Logarithmic Functions and Inverses
Logarithms and Logarithmic Functions
Aim: What is the logarithms?
8-3 Logarithmic Functions as Inverses
Which plan yields the most interest. Invest $100 Plan A: A 7
Algebra 2 Warmup.
6.3 Logarithms and Logarithmic Functions
4 minutes Warm-Up Write each expression as a single logarithm. Then simplify, if possible. 1) log6 6 + log6 30 – log6 5 2) log6 5x + 3(log6 x – log6.
6.1 - Logarithmic Functions
Growth Factor (b) = 1 ± Growth Rate (r)
Logarithmic Functions
Presentation transcript:

Evaluating Logarithms Section 4.4 Notes Evaluating Logarithms

Do-Now: Homework Quiz 1. Phil is trying to build up his endurance so that he can run a marathon. Right now he is able to run 4 miles at a time. Each week he wants to increase his distance by 15%. How far will he be able to run after 13 weeks? Bonus: Is this far enough to finish the marathon? 2. Ralph weighs 350 pounds. He is trying to lose 3% of his body weight every month. Write an equation to represent his weight, y, after x months. How much will he weigh after 16 months?

Units of Measurement For each of the following, give an example of the units of measurement that you might use. 1. speed 2. length 3. weight/force 4. temperature 5. launch angle 6. energy 7. intelligence 8. Dancing ability on DWTS 9. time 10. mass 11. force of electricity

Other measurement scales How do we measure….. 1. Strength of earthquakes Richter scale 2. Intensity of sound volume Decibels 3. Acidity pH scale 4. camera lens speed F-stop

Logarithmic Scales The previous examples all used logarithmic scales. An increase of one unit corresponds to a multiplication of another unit. They are used to simplify calculations for numbers that vary greatly.

Solve the following equations. 1. 5x – 14 = 8 2. 3x3 = 48 3. 4x2 – 12 = 3x2 + 13 4. 5 ∙ 10x = 120

Logarithms What method did you use in #1-3 that you were unable to use in number 4? Logarithms are the inverse operation for an exponential function.

Definition of logarithm logby = x is in logarithmic form bx = y is in exponential form They are equivalent expressions.

Examples Remember that log381 = 4 because 34 = 81. Calculate the following. 1. log464 2. log232 3. log1/525 4. log642 5. log99

Common log and natural log When a log has the base 10, we call it common log or just log. (log10x = log x) What is log 10,000? What is log .001? When a log has the base e, we call it natural log or ln. What is ln 50? (use your calculator) Log and ln are the only logarithms that you can do directly in the calculator.

Logarithms and Exponential Functions as Inverses. Again, logbx and bx are inverse functions. With that in mind, simplify the following. 1. log 105 2. eln 12 3. log8 84 Sometimes you have to rewrite a number so that the log base and the exponent base are the same. 4. log 100x 5. log327x

Finding Inverses Find the inverse of the following functions. 1. y = 8x 2. y = ln (x – 4)