Pre-calc w-up 4/10-11 Write the equation loge 13.7 = x in exponential form Write the equation (1/4)-4 = 256 in log form Evaluate the expression log443.

Slides:



Advertisements
Similar presentations
Today’s Date: 3/25/ Applications of Logarithms.
Advertisements

Essential Question: What are some of the similarities and differences between natural and common logarithms.
Copyright © 2009 Pearson Education, Inc. CHAPTER 5: Exponential and Logarithmic Functions 5.1 Inverse Functions 5.2 Exponential Functions and Graphs 5.3.
Warm-Up. One way to solve exponential equations is to use the property that if 2 powers w/ the same base are equal, then their exponents are equal. For.
8.4 Logarithms p. 486.
Solving Exponential Equations. One-to-One Properties.
Slide Copyright © 2012 Pearson Education, Inc.
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”
Warm-Up 5/6 1. Find the value of 2. Solve ,625.
Exponential and Logarithmic Equations
Section 3.4. Solving Exponential Equations Get your bases alike on each side of the equation If the variable is in the exponent set the exponents equal.
Objectives Solve exponential and logarithmic equations and equalities.
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”
11.3 – Exponential and Logarithmic Equations. CHANGE OF BASE FORMULA Ex: Rewrite log 5 15 using the change of base formula.
8.5 – Exponential and Logarithmic Equations. CHANGE OF BASE FORMULA where M, b, and c are positive numbers and b, c do not equal one. Ex: Rewrite log.
Warm-Up 4/30 Answer: $62, $60, Logarithmic Functions  The inverse of y = b x is _______  The function x = b y is called a___________.
Solving Exponential and Logarithmic Equations Section 8.6.
 If m & n are positive AND m = n, then  Can solve exponential equation by taking logarithm of each side of equation  Only works with base 10.
Unit 5: Modeling with Exponential & Logarithmic Functions Ms. C. Taylor.
Notes Over 8.4 Rewriting Logarithmic Equations Rewrite the equation in exponential form.
Solve logarithmic equations
Exponentials without Same Base and Change Base Rule.
Solving Logarithmic Equations
Aim: Exponential Equations using Logs Course: Alg. 2 & Trig. Aim: How do we solve exponential equations using logarithms? Do Now:
Logarithms 1 Converting from Logarithmic Form to Exponential Form and Back 2 Solving Logarithmic Equations & Inequalities 3 Practice Problems.
Evaluating Logs and Antilogs Warm-up Solve: Learning Objective: to evaluate and solve equations with logs of bases other than those we’re used to.
Unit 5: Logarithmic Functions
SOLVING LOGARITHMIC EQUATIONS Objective: solve equations with a “log” in them using properties of logarithms How are log properties use to solve for unknown.
7.4 Logarithmic Functions Write equivalent forms for exponential and logarithmic equations. Use the definitions of exponential and logarithmic functions.
6.10/6.11 Laws of Logarithms and change of base formula.
Solving Logarithmic Equations
Section 5.5 Solving Exponential and Logarithmic Equations Copyright ©2013, 2009, 2006, 2001 Pearson Education, Inc.
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.
Properties of Logarithms and Common Logarithms Sec 10.3 & 10.4 pg
3.3 Logarithmic Functions and Their Graphs
Lesson 10.2Logarithmic Functions Logarithm: Inverse of exponential functions. “log base 2 of 6” Ex: Domain: x>0 Range: all real numbers Inverse of exponential.
5.0 Properties of Logarithms AB Review for Ch.5. Rules of Logarithms If M and N are positive real numbers and b is ≠ 1: The Product Rule: log b MN = log.
Unit 5: Logarithmic Functions Inverse of exponential functions. “log base 2 of 6” Ex 1: Domain: all real numbers Range: y > 0 “log base b of x” Domain:
Warm – up #4. Homework Log Fri 2/5 Lesson 6 – 4 Learning Objective: To solve log and exponential equation Hw: #605 Pg. 369 #1 – 49 odd.
Logarithms – Solving, Inverses, and Graphs To graph a logarithmic function simply enter it into your calculator: Graph y = log 10 x Since your calculator.
3.4 Solving Exponential and Logarithmic Equations.
10.14 Applications of Logarithms. Ex 1) Solve log x = Round to 4 decimal places Remember: Common log = base 10 log 6 = log 10 6 x =
8.5 – Exponential and Logarithmic Equations
Ch. 8.5 Exponential and Logarithmic Equations
8-5 Exponential and Logarithmic Equations
6.1 - Logarithmic Functions
Solving Exponential and Logarithmic Equations
8.5 – Exponential and Logarithmic Equations
Exponential and Logarithmic Equations
Logarithmic Functions and Their Graphs
Logarithmic Functions
6.5 Applications of Common Logarithms
6.4 Logarithmic & Exponential Equations
Unit 8 [7-3 in text] Logarithmic Functions
5.4 Logarithmic Functions and Models
Logarithms and Logarithmic Functions
Logarithmic Functions
7.6 Solve Exponential and Logarithmic Equations
LEARNING GOALS – LESSON 7.5
5A.1 - Logarithmic Functions
Logarithmic and Exponential Equations
Solve for x: 1) xln2 = ln3 2) (x – 1)ln4 = 2
Logarithmic and Exponential Equations
3.4 Exponential and Logarithmic Equations
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
Warm Up  .
Logarithmic Functions
Presentation transcript:

Pre-calc w-up 4/10-11 Write the equation loge 13.7 = x in exponential form Write the equation (1/4)-4 = 256 in log form Evaluate the expression log443 Solve log2x + log210 = log270

A common logarithm is a logarithm with a base of 10. log10x = logx 11.5 Common Logarithms A common logarithm is a logarithm with a base of 10. log10x = logx

Ex 1: Given log8 = 0.9031 evaluate Use your properties of logarithms to simplify. Remember a logarithm is an exponent. Ex 1: Given log8 = 0.9031 evaluate A) log 800,000 = log (100,000 x 8) = log 105 + log 8 = 5 + 0.9031 = 5.9031

The antilog… The inverse of a logarithm is a _______ So if log x = a then ________ What… Log 11.5=_________ Antilog 1.06069784 = _____________ Try these 2a) log 54.1 2b) antilog1.9484 Answers 1.7332 88.7973 exponent 10a = x 1.06069784 – push the buttons on your calc 11.5 on calc push 2nd log 10^1.06069784 (inverse of log)

Change of base – we want base 10 then we can use our calculators. a,b,n are positive and a and b don’t equal 1 then the change of base formula is… Ex 3: find the value of log9 1043

Use logs to solve exponential functions.. Ex4: solve 63x = 81 Take the log of both sides log63x = log 81 “finding answers in the hunt powers of log can go up front” 3x log 6 = log 81 (now solve) 3x = log81/log6 (divided both sides by log6) x = .8175 (divided both sides by 3)

Ex 5: 12x-4 = 3x-2 Take the log of both sides, bring powers up front (x – 4)log12 = (x – 2) log3 You can NOT distribute the log, a log is an exponent Do you do this (x + 5)2 = x2 + 25 NO Divide by a log 1st, (doesn’t matter which one) then follow rules of solving. x = 5.58 

Ex6: graph y= 3log(x+1) What is the basic shape of a logarithm? Type it into your calc y = logx How does that compare to y = 10^x? Plug into your calculator, adjust window, label at least 3 points.

Remember: Logs in real number system are undefined for negative numbers. You can get a negative answer, you can’t take a log of a negative number Homework: pg 730 # 19-21,23,28 – 45 all 19-23 NO CALC 28-rest you can use a calculator