Math 142 Lecture Notes for Section 6.1 Section 6.1 - Antiderivatives Example 6.1.1: List any function whose derivative is x. Example 6.1.2: List any function whose derivative is x3 + 5. 1 Math 142 Lecture Notes for Section 6.1 2 Definition 6.1.3: The General antiderivative of f (x) on an interval I is the function F (x) + C where C stands for any real number, if Also written as which is known as the indefinite integral of f (x), where F 0 (x) = f (x). General Rules of Integration: Z (1) xn dx = Z (2) kdx = Z (3) Z (4) ex dx = 1 dx = x Z (5) [f (x) + g(x)]dx = Z (6) [k · f (x)]dx = Math 142 Lecture Notes for Section 6.1 Example 6.1.4: Find the following: Z (a) 3dx = Z (b) Z 1 4 x dx = 3 Z 2 dt = t7 (c) (d) Z (e) Z (f) x5 dx = (5x3 + 2x2 + 3)dx = 4 dx = x 3 Math 142 Lecture Notes for Section 6.1 Z (g) (ex + x2 )dx = Z √ 1 (2 x − 3 + x4/7 )dx = x Z 4x3 + 6x2 dx = 2x (h) (i) Z (j) (x + 4)(x − 3)dx = Example 6.1.5: Find y if y(1) = 3 and dy 6 1 = − 3 dx x x 4 Math 142 Lecture Notes for Section 6.1 5 Example 6.1.6: The daily marginal cost function for the Stark Iron Buddy prototype is given by M R(x) = 2 10 − x3 for 0 ≤ x ≤ 1000, where x represents the number of Iron Buddies produced. (a) Suppose that R(3) = $120, find the revenue function for Iron Buddies. (b) Using the information given and the fact that R(x) = p(x)·x give the price function for Iron Buddies. (c) What will the price be when the demand is for 300 Iron Buddies? Section 6.1 Suggested Homework: 1-47 (odd)