A.5 Converses, inverses, and contrapositive
Look at the following conditionals:
If Roy does a cartwheel, then Lee does not stand on his head.
If Lee stands on his head, then Roy does not do a cartwheel.
Is the second conditional the contrapositive, converse, or inverse of the first conditional?
contrapositive
converse
inverse
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Answer :

Sure, let's analyze the given conditionals step-by-step.

### Step 1: Define the Propositions
We start by defining the propositions of the original conditional statement:

- Let [tex]\( P \)[/tex]: "Roy does a cartwheel."
- Let [tex]\( Q \)[/tex]: "Lee does not stand on his head."

### Step 2: Original Conditional Statement
The original statement can be written formally as:
[tex]\[ P \rightarrow Q \][/tex]
(If Roy does a cartwheel, then Lee does not stand on his head.)

### Step 3: Forms of Related Conditionals
We need to examine the second conditional and decide whether it is the contrapositive, converse, or inverse of the original.

#### Inverse
The inverse of the original statement [tex]\( P \rightarrow Q \)[/tex] is:
[tex]\[ \neg P \rightarrow \neg Q \][/tex]
(If Roy does not do a cartwheel, then Lee stands on his head.)

#### Converse
The converse of the original statement [tex]\( P \rightarrow Q \)[/tex] is:
[tex]\[ Q \rightarrow P \][/tex]
(If Lee does not stand on his head, then Roy does a cartwheel.)

#### Contrapositive
The contrapositive of the original statement [tex]\( P \rightarrow Q \)[/tex] is:
[tex]\[ \neg Q \rightarrow \neg P \][/tex]
(If Lee stands on his head, then Roy does not do a cartwheel.)

### Step 4: Analyze the Second Conditional
The second conditional statement is:
"If Lee stands on his head, then Roy does not do a cartwheel."

This can be rewritten in propositional form as:
[tex]\[ \neg Q \rightarrow \neg P \][/tex]

### Step 5: Compare and Identify
Now, we compare the second conditional with the forms we identified previously:

- The second conditional ([tex]\( \neg Q \rightarrow \neg P \)[/tex]) matches the contrapositive of the original conditional.

### Conclusion
Therefore, the second conditional is the contrapositive of the first conditional.

The answer is:
[tex]\[ \text{contrapositive} \][/tex]

Thus, the correct choice is:
[tex]\[ \boxed{contrapositive} \][/tex]