Proof Techniques - Direct Proofs

Section 2.1 Materials

Section 2.1 Problem Set

Section 2.1 Basic Comprehension Quiz

Section 2.1 Screencasts

Please note that if you are having buffering issues or slow response times for the videos or video controls, this can be alleviated by downloading the video. There is a "Download" button below the viewing screen of each video.

Section 2.1 Supplemental Videos

Here is a selection of supplemental videos related to topics in this section.

• Working with definitions (Screencast 1.2.1),
• Working with definitions, part 2 (Screencast 1.2.1b),
• Direct proofs of conditional statements using know-show tables (part 1) (Screencast 1.2.2),
• Direct proofs of conditional statements using know-show tables, Part 2 (Screencast 1.2.3)
• Integer divisibility (Screencast 3.1.1),
• Direct proof involving divisibility (Screencast 3.1.2),
• Integer congruence (Screencast 3.1.3),
• Reducing an integer modulo n (Screencast 3.1.4),
• Proofs involving integer congruence (Screencast 3.1.5),
• Proof of biconditional statements (Screencast 3.2.3),
• Proof of biconditional statements, part 2 (Screencast 3.2.4),
• Constructive proofs (Screencast 3.2.5)

These videos were created by Robert Talbert from the Mathematics Department at Grand Valley State University. Click here for more details.