Fill in the following derivation. You may use any rule from SD+ or PD+.
- To type a universal quantifier, e.g., (^x),
or an existential quantifier, like (%y),
you can leave out the parentheses. They will be added in after you've moved
on to the next field.
- You may use the standard typing shortcuts,
i.e., you need not use the shift key to get the computer to know you
mean '&', '(', etc.
- Slash shortcuts : For all rules of
inference of SL you may type the justification, TAB, then type
'/' or '//' and TAB. The answer you intended will likely appear!
This will not work for PL rules: we need to learn to do these on our
- You may do more than one problem on this page.
At any time you would like to start a new problem and give it a name just
type "new" into the justification field. You'll be prompted for
(As always, if you have questions, send me an e-mail at firstname.lastname@example.org
or use the course discussion