7.1 Antiderivatives OBJECTIVES * Find an antiderivative of a function. *Evaluate indefinite integrals using the basic integration formulas. *Use initial conditions, or boundary conditions, to determine an antiderivative. Slide

Who comes up with the ready-made functions we find derivatives for? Isn’t it hard sometimes to find a function for total cost, profit, etc.? Sometimes it is easier to calculate the rate of change of something and get the function for the total from it. This process, the reverse of finding a derivative, is antidifferentiation. Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 1: Can you think of a function that would have x 2 as its derivative? Antiderivatives

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley One antiderivative is x 3 /3. All other antiderivatives differ from this by a constant. So, we can represent any one of them as follows: To check this, we differentiate.

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley THEOREM If two functions F and G have the same derivative over an interval, then F(x) = G(x) + C, where C is a constant. Antiderivatives

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Antiderivatives Integrals and Integration Antidifferentiating is often called integration. To indicate the antiderivative of x 2 is x 3 /3 +C, we write

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Antiderivatives The notation is used to represent the antiderivative of f (x). More generally, where F(x) + C is the general form of the antiderivative of f (x).

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley THEOREM : Basic Integration Formulas

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 2: Evaluate 4.2 Area, Antiderivatives, and Integrals

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Check:

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 3: Evaluate 4.2 Area, Antiderivatives, and Integrals

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Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley THEOREM 4 (The integral of a constant times a function is the constant times the integral of the function.) (The integral of a sum or difference is the sum or difference of the integrals.) 4.2 Area, Antiderivatives, and Integrals

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 4: Evaluate 4.2 Area, Antiderivatives, and Integrals

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 5: Evaluate and check by differentiation: 4.2 Area, Antiderivatives, and Integrals a) 7 e 6 x  x   dx ; b) 1  3 x  1 x 4        dx ;

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Antiderivatives Example 5 (concluded):

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 5 (continued): Check: Antiderivatives

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 5 (continued): Antiderivatives

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 5 (concluded): Check: Antiderivatives

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 6: Find the function f such that First find f (x) by integrating. Antiderivatives

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley Example 6 (concluded): Then, the initial condition allows us to find C. Thus, Antiderivatives

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley

Slide Copyright © 2008 Pearson Education, Inc. Publishing as Pearson Addison-Wesley