Unit 3 Flashcards
What is the negation of m∠1 + m∠2 = 90°?
m∠1 + m∠2 ≠ 90°
What is the negation of x is purple?
x is not purple
What is the negation of x + 7 ≠ 5?
x + 7 = 5
What is the negation of ∠1 & ∠2 are not complementary?
Ð1 & Ð2 are complementary
What is the negation of x – 5 ≤ 7?
x – 5 > 7
What is the negation of m∠1 < m∠2?
m∠1 ≥ m∠2
What letters are used for hypothesis and conclusion?
p - hypothesis q - conclusion
What are the three ingredients needed for a good counterexample?
- Must work for hypothesis 2. Must not work for conclusion 3. Must be specific
For any conditional statement, how do you find the converse?
Switch the hypothesis and conclusion
For any conditional statement, how do you find the inverse?
Negate the hypothesis and conclusion
For any conditional statement, how do you find the contrapositive?
Switch and negate the hypothesis and conclusion
What words do we use to write any biconditional?
If and only if (iff)
How do you determine the truth value of any biconditional?
If both conditionals are true then the biconditional is true - if either conditional is false, then the biconditional is false
What does it mean for statements to be “logically equivalent”?
They have the same truth value, justification if true, and counterexample if false
How do you write a logically equivalent statement to any conditional statement?
Switch and negate the hypothesis and conclusion