3.1 Topics: Antiderivatives and Indefinite Integration Solutions Find the indefinite integral ( don’t forget the + C ). You may need to rewrite the integrand prior to integrating. Simplify your answer if possible (do not factor your answer but do rewrite your answer so that there are no negative exponents). 1 1. x 3 dx 2 x 2. x 3. 4. 2x 4 2 3x C 3x 2 x 4 dx 1 3 x dx x 3 dx 1 3 1 5 1 x x3 x 2 4 x C 5 2 3 34 x C 4 1 1 1 1 dx x 3 dx x 2 C 2 C 2 2 2 4x 1 1 1 12 6 2 32 2 32 x 2 2 2 dx dx x 6 x dx x 6 2 x C x 12 x C 3 3 x x x x6 5. 6. x 1 2 x 3 dx 2 x 7. y 8. dx 1dx x C 9. 2 cos x 3sin x dx 2sin x 3cos x C 2 1 2 1 1 2 5 5 x 3dx 2 x 3 5 x 2 3x C x 3 x 2 3 x C 3 2 3 2 5 y dy y 2 y 2 dy y 2 dy 2 72 y C 7 10. 2 csc x cot x dx 2 x csc x C 11. tan 12. x x dx 2 x 2 1 d sec2 d tan C 4 1 2 4ln x C 1 2 x ln x 4 C 2 13. A ball is thrown vertically upward from a height of 6 feet with an initial velocity of 60 feet per second. How high will the ball go. Use a t 32 ft 2 s a t 32 ft 2 v t a t dt v t 32dt v t 32t C s since we are told the intital velocity is 6o feet per second we know that v 0 60 v 0 32 0 C 60 C 60 So our velocity function is v t 32t 60. At the maximum height the velocity will be zero.... 0 32t 60 t 1.875sec So if we want to know what the maximum height is we need to find the position function for this problem and evaluate it at t 1.875sec. s t v t dt 32t 60 dt 16t 2 60t C. So were told that the ball was thrown from an initial height of 6 feet so we know that when t=0 the position was 6 ft. 6 16 0 60 0 C C 6. So our position function is s t 16t 2 60t 6 2 s 1.875 16 1.875 60 1.875 6 62.25 ft 2 14. With what initial velocity must an object be thrown upward (from ground level) to reach the top of the Washington Monument (approximately 500 feet)? If the object is thrown upward from ground level we know that its initial position was zero. So our position equation will be s t 16t 2 v0t 0 . If 500 feet is to be the peak of the object’s path then the velocity at the peak will be zero so v t 32t v0 0 32t v0 t v0 32 Now we will set s(t)=500 … 500 16t 2 v0 t and set t v0 and we will be able to solve for the initial velocity. 32 2 v2 v2 v v 500 16 0 v0 0 500 0 0 64 32 32 32 v0 32000 178.89 ft s 500 Answer: v0 178.89 v0 2 64 32000 v0 2 ft s 15. A baseball is thrown upward from a height of 2 meters with an initial velocity of 10 m . Determine its maximum height. s Use a t 9.8 m 2 s This problem is similar to 13 except the units are different. a t 9.8 m 2 v t a t dt v t 9.8dt v t 9.8t C s m Since the initial velocity is 10 we have v 0 9.8 0 C 10 C 10 s v t 9.8t 10 s t v t dt s t 9.8t 10 dt s t 4.9t 2 10t C Since the initial height is 2 meters we have 2 4.9 0 10 0 C C 2 2 so s t 4.9t 2 10t 2. At the maximum height the velocity will be zero... v t 9.8t 10 0 which gives us a time of t 2 10 9.8 10 10 10 s 4.9 10 2 7.1m 9.8 9.8 9.8