Questioning Strategies Analytic Geometry Student Notes 1.4 AKS: Identify, write, and analyze conditional statements. What should you be able to do? Identify, write, and analyze the truth value of conditional statements. Write the inverse, converse, and contrapositive of a conditional statement. When the word then does not appear in a conditional statement, how can you tell which part is the conclusion? Example: Identify the hypothesis and conclusion of each conditional. a) If today is Thanksgiving Day, then today is Thursday. Hypothesis (p): _________________________________________ Conclusion (q): _________________________________________ b) A number is a rational number if it is an integer. Hypothesis (p): _________________________________________ Conclusion (q): _________________________________________ A conditional statement has a truth value of either true (T) or false (F). It is false only when the hypothesis is true and the conclusion is false. What are the steps you should take to determine the truth value of a conditional statement? To show that a conditional statement is false, you need to find only one counterexample where the hypothesis is true and the conclusion is false. Example: Determine if the conditional is true. If false, give a counterexample. a) If this month is August, then next month is September. Hypothesis: _______________ Conclusion: ________________ _______________________________________________________ b) If two angles are acute, then they are congruent. Hypothesis: _______________ Conclusion: ________________ _______________________________________________________ c) If the sky is green, then 5 + 4 = 8. Hypothesis: _______________ Conclusion: ________________ _______________________________________________________ Make a table that shows all the combinations of truth values for the hypothesis and conclusion and the resulting truth values of the conditional statement. Explain a way to help you remember this. Questioning Strategies Analytic Geometry Student Notes 1.4 The negation of statement p is “not p,” written as ~p. The negation of a true statement is false, and the negation of a false statement is true. What are the chances that either event p or event ~p will occur? Explain. Example: Write the negation of the following statements. a) The answer is seven. _______________________________________________________ b) The water was hot. _______________________________________________________ Example: Write the converse, inverse, & contrapositive of the conditional statement, than find the statement’s truth value: If you go to Central Gwinnett, then you are a Black Knight. p: ________________________________________________________ q: ________________________________________________________ Converse: __________________________________________________ ______________________________________ Truth Value: ________ Inverse: ___________________________________________________ ______________________________________ Truth Value: ________ Contrapositive: ______________________________________________ ______________________________________ Truth Value: ________ Draw Example 1b as a Venn Diagram. Many sentences without the words if and then can be written as conditionals. To do so, identify the sentence’s hypothesis and conclusion by figuring out which part of the statement depends on the other. Example: Write a conditional statement from the following. a) An obtuse triangle has exactly one obtuse angle. ______________________________________________________ ______________________________________________________ b) ____________________________ ____________________________ ____________________________ How can you remember the characteristics of the converse, inverse, and contrapositive of a conditional statement?