The Brief but Handy AP Calculus AB Book 0011 0010 1010 1101 0001 0100 1011 By Jennifer Arisumi & Anug Saha 1 2 4 Table of Contents 0011 0010 1010 1101 0001 0100 1011 What is a limit?……………………………………………..…………………….4 What does it mean for a limit to exist?...................................5 How limits fail to exist………………………………………………………...6 Finding the limit graphically…………………………………………………7 Finding the limit numerically and algebraically .…………………8 Definition of Continuity at a Point……………………………………….9 How limits impact the continuity of a function ..………....10-11 Derivatives ………………………………………………………………….12-13 Examples and Practice…………………………………………….…………14 Antiderivatives ..………………………………………………………….……15 1 2 4 Table of Contents 0011 0010 1010 1101 0001 0100 1011 Indefinite and Definite Integrals ……………………………………….16 Fundamental Theorems of Calculus..…………………………………17 Common Integrals and Basic Properties/Formulas/Rules…..18 Examples and Practice ……………………………………………………..19 Application Problem …………………………………………………………20 About the Authors ……………………………………………………….21-22 Bibliography ………………………………………………………………….....23 The End……………………………………………………………………………..24 1 2 4 What is a limit? 0011 0010 1010 1101 0001 0100 1011 • The limit of f(x) as x approaches a is L lim 𝑓 𝑥 = 𝐿 𝑥→𝑎 1 2 Let y=f(x) be a function. Suppose that a and L are #’s such that: • Whenever x is close to a but not equal to a, f(x) is close to L • As x gets closer and closer to a, but not equal to a, f(x) gets close to L 4 4 What does it mean for a limit to exist? 0011 0010 1010 1101 0001 0100 1011 For a limit to exist, three criteria must be met if 1 2 1. lim 𝑓 𝑥 exists → lim from the right exists 𝑥→𝑎+ 4 2. lim 𝑓(𝑥) exists → lim from the left exists 𝑥→𝑎− 3. lim 𝑓(𝑥) = lim 𝑓(𝑥) = L 𝑥→𝑎+ 𝑥→𝑎− 5 How limits fail to exist 0011 0010 1010 1101 0001 0100 1011 • A limit fails to exist when x approaching to a is not the same from the left and the right 1 6 2 4 Finding the limit graphically 0011 0010 1010 1101 0001 0100 1011 1 𝑥 2 +1 lim 𝑥→−1 𝑥+1 7 = -1 2 4 Finding the limit numerically and algebraically 0011 0010 1010 1101 0001 0100 1011 Numerically: 𝑥 2 −3𝑥+2 lim 𝑥→2 𝑥−2 x 1.75 1.9 1.99 1.999 2 2.001 2.01 f(x) .75 .9 .99 .999 1 1.001 11.01 = (𝑥−2)(𝑥−1) (𝑥−2) Algebraically: 1.Factor 2.Simplify 3.Substitute 𝑥 2 −3𝑥+2 lim 𝑥→2 𝑥−2 lim 𝑥 − 1 𝑥→2 =2-1 =1 8 = x-1 2.1 1 1.1 2.25 2 1.25 4 Definition of Continuity at a Point 0011 0010 1010 1101 0001 0100 1011 A function is continuous at a point c if: (a) f(c) is defined 1 (b) lim 𝑓(𝑥) exists 𝑥→𝑐 (c) lim 𝑓(𝑥) = f(c) 𝑥→𝑐 9 2 4 How limits impact the continuity of a function 0011 0010 1010 1101 0001 0100 1011 Continuity at a point and on an open interval: • f is continuous means: no interruption in the graph of the function of “f” at “c” • the f is continuous also means: there is no gap, holes, or jumps in the graph 1 10 2 4 Continuity Continue… 0011 0010 1010 1101 0001 0100 1011 1 𝑥→4 continuous because it has a gap at point 4 11 2 4 f(x) = 𝑥 3 − 6𝑥 2 − 𝑥 + 30 lim 𝑥 3 − 6𝑥 2 − 𝑥 + 30 has a limit but is not Derivatives 0011 1010 1101 0001 0100 1011 rate of change of a function with respect • 0010 The derivative is the instantaneous to one of its variables or the slope of a point on a given function. In algebra, you can determine the slope of a line by taking two points on that line and plug them into the slope formula: 1 2 • But in Calculus we no longer want to find the slope of a line but the slope of a point of a given curve. To do that we would set up the definition of the Derivative which is a slightly modified version of the slope formula but the only difference is that we’re finding the slope between two points that are infinitely close to each other. 12 4 Derivatives Continue… • Finding the derivative using the definition of the derivative is a process that is 0011 0010 1010 1101 0001 0100 1011 very time consuming and sometimes involves a lot of complex algebra. Fortunately, there’s a short cut to finding a derivatives! • Here are some common derivatives: 1 13 2 4 Examples and Practice 0011 0010 1010 1101 0001 0100 1011 1. Solution: 1 2. Solution: 3. Solution: 14 2 4 Antiderivatives 0011 0010 1010 1101 0001 0100 1011 • Antiderivatives are exactly how they sound- they are the opposite of derivatives. Or they can be know as the step before you take the derivative. It basically means that you take the function that you are given and say that it is the derivative, and figure out what function it is the derivative of. • Integrals are basically anti-derivatives, set into a formula designed to tell you to take the antiderivative. There are two types of integrals, indefinite and definite integrals. 1 15 2 4 Indefinite and Definite integrals 0011 0010 1010 1101 0001 0100 1011 • Indefinite integrals: Simply an antiderivative. Example: • Definite integrals: The definite integral of f(x) is a number and represents the area under the curve of f(x) from a to b on the x axis. Example: 1 16 2 4 Fundamental Theorems of Calculus 0011 0010 1010 1101 0001 0100 1011 • First FTC: f(x) is continuous on [a,b] , F(x) is an antiderivative of f(x) then 1 • Second FTC: If f(x) is continuous on [a,b] then F´(x)= f(x) when 17 2 4 Common Integrals and Basic Properties/Formulas/Rules 0011 0010 1010 1101 0001 0100 1011 1 18 2 4 Examples and Practice 0011 0010 1010 1101 0001 0100 1011 1. Solution: 1 2. Solution: 3. Solution: 19 2 4 Application Problem 0011 0010 1010 1101 0001 0100 1011 The graph of the velocity function is shown in Figure 9.3-2. 1. When is the acceleration 0? 2. When is the particle moving to the right? 3. When is the speed the greatest? 1 2 4 Solution: 1. a(t) = v'(t) and v'(t) is the slope of tangent to the graph of v. At t =1 and t =3, the slope of the tangent is 0. 2. For 2 < t < 4, v(t) > 0. Thus the particle is moving to the right during 2 < t < 4. 3. Speed = |v(t)| at t =1, v(t) = – 4. Thus, speed at t = 1 is |–4| = 4 which is the greatest speed for 0 ≤ t ≤ 4. 20 About the Author Anug Saha 0011 0010 1010 1101 0001 0100 1011 Anug Saha is a Indian-Bangali male who was born and raised in Astoria, NY. He still has no clue in what he wants to do with his life but he knows he wants math to be involved. He hopes that the University of Wisconsin - Madison can shape him into the person his parents would be proud of. He loves food and the presence of his friends. He knows he will be a big deal one day. 21 1 2 4 About the Author Jennifer Arisumi 0011 0010 1010 1101 0001 0100 1011 Jennifer Arisumi is a junior at the High School for Environmental Studies. She is a very outgoing bright student. Her favorite subject is math and hopes that in her future math would be involved. She hasn’t decided yet what she wants to be in the future but she knows it wants to be something related to animals. She loves food and making new friends. 22 1 2 4 Bibliography 0011 0010 1010 1101 0001 0100 1011 • http://archives.math.utk.edu/visual.calculus/1/definition. 6/ • http://physics.info/kinematics-calculus/problems.shtml • https://benchprep.com/blog/ap-calculus-topics-limits/ • Textbook • class notes 1 23 2 4 0011 0010 1010 1101 0001 0100 1011 The End 24 1 2 4