1 00:00:03,378 --> 00:00:07,284 [MUSIC]. Welcome back to Calculus One. 2 00:00:07,284 --> 00:00:10,223 And welcome to Week 15 of our time together. 3 00:00:10,223 --> 00:00:14,997 We've been at this since January, and this is it, this is the last week of the 4 00:00:14,997 --> 00:00:18,590 course. Where are we? 5 00:00:18,590 --> 00:00:21,701 Last week in Week 14, we were working at techniques of integration and the 6 00:00:21,701 --> 00:00:25,920 technique that we focused on was integration by parts. 7 00:00:25,920 --> 00:00:29,690 This week in Week 15 we're looking at an application of integration, but which 8 00:00:29,690 --> 00:00:32,455 application? There's so many applications of 9 00:00:32,455 --> 00:00:36,410 integration that we could be looking at. We could fill up a whole Calculus Two 10 00:00:36,410 --> 00:00:39,949 course with various applications of the integral. 11 00:00:39,949 --> 00:00:42,705 The application that we've picked is volume. 12 00:00:42,705 --> 00:00:46,695 I think it's a ton of fun, to use integrals to calculate the volumes of 13 00:00:46,695 --> 00:00:51,610 solid three dimensional objects. It's fun because it gives us a chance to 14 00:00:51,610 --> 00:00:54,560 think geometrically, to think three-dimensionally, but I also think 15 00:00:54,560 --> 00:00:58,812 it's important historically. You know, thousands of years ago, the 16 00:00:58,812 --> 00:01:02,860 first inklings of a definite integral appeared, you know? 17 00:01:02,860 --> 00:01:06,552 People were thinking about taking objects and slicing them into really thin pieces, 18 00:01:06,552 --> 00:01:11,390 say infinitesimal pieces, and adding up all of those infinitesimal pieces. 19 00:01:11,390 --> 00:01:17,054 And the idea is really, really old. So, I think it's appropriate that we end 20 00:01:17,054 --> 00:01:21,056 this course with something at the very beginning of humankind's grasping towards 21 00:01:21,056 --> 00:01:25,282 the definite integral. We're going to end this course with some 22 00:01:25,282 --> 00:01:28,980 volume calculations. It's also appropriate that we end this 23 00:01:28,980 --> 00:01:32,452 course for the final exam. The final exam is available right now, 24 00:01:32,452 --> 00:01:35,792 and you got until the beginning of May to finish it. 25 00:01:35,792 --> 00:01:44,844 Good luck.