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If you're currently enrolled in 311, be sure to go to the current quarter to see your homework assignments.
Assignments
| Assignment | Release Date | Due date |
|---|
| Homework 1 | Thur. January 4 | Thur. January 11, 11:59pm |
| Homework 2 | Wed. Jan 10 | Wed. January 17, 11:59pm |
| Homework 3 | Wed. Jan 17 | Wed. January 25, 11:59pm |
| Homework 4 | Wed. Jan 24 | Wed. January 31, 11:59pm |
| Homework 5 | Wed. Jan 31 | Wed. Feb 7, 11:59pm |
| Homework 6 | Wed. Feb 14 | Wed. Feb 21, 11:59pm |
| Homework 7 | Thur. Feb 22 | Wed. Feb 28, 11:59pm |
| Homework 8 | Thur. Feb 29 | Wed. Mar 6, 11:59pm / Fri. Mar 8, 11:59pm |
Typesetting
You are not required to typeset your homework solutions; however, it is an easy way to improve the legibility of your documents. Many Allen School students learned to typeset in this course.
LaTeX is the standard tool for typesetting mathematical materials. While it takes some time to learn, it will likely pay for itself in the long run. You can even use LaTeX in places like Ed and Facebook Messenger!
These resources may be helpful for you to get started with LaTeX, with thanks to Adam Blank:
Overleaf is an online editor that spares you from having to install LaTeX locally. Overleaf has some documentation, but you might want to read this how-to-overleaf document first.
Formatting
We get many questions about formatting -- we aren't as strict about formatting as your high school classes were (or your English classes likely are), but we do have some requirements to make grading easier for the TAs:
- Have every numbered problem start on its own page (so TAs can easily find where your answers start)
- We don't care if you restate the question or not, but do list the number and letter
- list your collaborators somewhere on the pdf that we can find (we don't have a specific requirement on where -- the first or last page are common choices)
- When you upload to gradescope, make sure you select pages and that the pages are right-side-up
- Putting your name on your submitted pdf is not required (Gradescope automatically associates your name to your submission). We prefer you don't put your own name on your submission (as it reduces the chances of unconscious bias for the graders), but it is not forbidden.
Guidelines
Inference Proofs (beginning on HW4)
- You may apply any other rule from the propositional logic reference sheet.
- You may apply commutativity, associativity, and double negation as many times as you want within a single step, provided you include that name in your rule. You may also combine these with other propositional logic rules, provided they are listed with the rule name.
- But you still must have a prior step in the correct order to “Eliminate OR”
- Include line numbers for the referenced step, but for rules with multiple numbers do not worry about the ordering.
- Abbreviated rule names (like “MP” for “Modus Ponens”, or “Intro” for “Introduce”) are acceptable as long as they are clear.
- Remember to indent and change numbering style (e.g. from 2 to 3.1) when starting a subproof.
- You may introduce variables as arbitrary with a separate step (provided they are truly arbitrary), but it is not required if it is a fresh variable introduced from eliminating a for-all.
Symbolic Proofs (using equivalence rules or boolean algebra)
Symbolic proofs are part of the “training wheels phase” of proof writing. Follow these rules when you write your first symbolic proofs:
- Apply only one rule per step, and label each step with the name of the rule you applied.
- Respect order of operations. Operations are applied in precedence order, going from left to right across an expression. Be careful that you aren’t violating “implied” parentheses.
- Make sure you are applying the rule exactly as stated in the handout. The handout rules apply to compound propositions, as long as order of operations allow their application.
- The associative law, commutative law, or double negation law may be applied multiple times in a single step as long as you specify that it was applied repeatedly (e.g., “associative law twice”). For these proofs, do not combine them with other laws.
Homework in General
We evaluate your work using these guiding principles:
- Legibility. You may lose points for solutions that are not legible. We cannot award points for solutions that we cannot easily read. Please consider typesetting!
- Clarity. Remember to be mathematically formal and jot down your thoughts and assumptions. A proof is seldom strictly right or wrong; instead, it is only as convincing as the extent your human reader is convinced.
- Style. This can be subjective, but it mostly boils down to organizing your work to make it easy to follow. Make sure you set up consistent notations beforehand, communicate information concisely (unlike this), and give your work a good proofread from start to finish.
You can submit a regrade request on individual problems after we release feedback. Regrades will be open for a week.
We will not debate the amount of points deducted for mistakes. Those are entirely at the discretion of the course staff.