Chapter 2 Logic

Question 1

What is logic?

Answer 1

The study of reasoning.

Question 2

Mathematical sentence

Answer 2

A sentence that is either true or false, not an opinion.

Question 3

Open sentence

Answer 3

A sentence with a variable. When you replace the variable it can become either true or false depending on what you replace with.

Question 4

Compound sentence

Answer 4

Two or more mathematical sentences combined with a connector word.

Question 5

Conjunction

Answer 5

AND only true if both parts are true.

Question 6

Disjunction

Answer 6

OR only true if one or more parts are true.

Question 7

Conditional

Answer 7

If… Then… Only false when they lied… If false then true. =false

Question 8

Logical structure

Answer 8

The column on the truth table for that sentence. If two sentences have the same structure then they are logically equivalent.

Question 9

Negation

Answer 9

The opposite of the statement: I is one letter. Vs. I is not one letter.

Question 10

Inverse

Answer 10

Only works for conditional sentences: do the negation of both parts: not logically equivalent with the original.

Question 11

Converse

Answer 11

Only works for conditional sentences: put on your converse shoes and kick the sentence to make it flip over: not logically equivalent with the original.

Question 12

Contrapositive

Answer 12

Only works for conditional sentences: do the negation of both parts and flip it over: logically equivalent with the original.

Question 13

Detachment

Detachment

Answer 13

If a conditional is true and the hypothesis is true then the conclusion is true.

Question 14

Disjunctive Inference

Answer 14

If a disjunction is true and one part is false then the other part must be true.