stanford-introduction-to-mathematical-thinking
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adyavanapalli
There is some errors in the AS6 ex3 and ex4
@coolcty Can you point out which ones?
ex 3 bceghmn
we should repalce implication by logical 'and'
For exemple, 3 c, Some elephants do not like muffins. If all elephants like muffins, your symbolic statement is still true. In fact, we can take a as an animal who is not elephant, then the implication is still true for its sufficent condition is not satisfied.
ex 4 bceghmn
similar corresponding issues
I'm not convinced by @coolcty . I feel that implication should be used. Please correct me if I'm wrong.
An important thing to realize here is that the implication not only expresses the possibility when the elephants eat muffins but also when they don't. Our domain of interest is 'All animals' and not just 'Elephants'. So, while writing an implication, we also express the possibility when 'there exists 'a' and 'a' is not an elephant and it likes/dislikes muffins'. Then also the statement will be true.
When we say 'Some elephants like muffins' it also means that 'Some animals like muffins'. It also means that there may be some animals/elephants that may not be liking muffins. Only implication can express this.
