9. Let the domain of x and y be all SCU students L(x, y) denotes that x likes y C(x, y) denotes that x and y are in a club together G(x) denotes x pops gum Express in logic 1. There is a student who likes all other students but is in a club with none of them 2. No one likes a gum popper

10. Let the domain of x and y be all SCU students L(x, y) denotes that x likes y C(x, y) denotes that x and y are in a club together G(x) denotes x pops gum N(x, y) denotes that x and y have the same first name Express in logic 1.There is a student who likes all other students but is in a club with none of them 1.5. There is a student who likes all other students but has the same first name as none of them 2. No one likes a gum popper

11. Vocab An argument is a sequence of statements, ending with a conclusion Premises are the statements, aka the assumptions An argument is valid if, whenever the premises (assumptions) are true, then the conclusion is true Note: An argument is different from a proof. A valid argument with false premise(s) can lead to a false conclusion!

13. Assumptions When Jane eats sauerkraut, Bob complains If Bob smells cookies or is happy, he doesn’t complain If Bob is unhappy, he eats Ben and Jerry’s Chunky Monkey ice cream Jane is eating sauerkraut

14. Assumptions When Jane eats sauerkraut, Bob complains If Bob smells cookies or is happy, he doesn’t complain If Bob is unhappy, he eats Ben and Jerry’s Chunky Monkey ice cream Jane is eating sauerkraut