$\{\text{integers $n$ such that $n$ is even}\}$
It can be true/false so does that mean it's proposition/mathematical statement?
$\{\text{integers $n$ such that $n$ is even}\}$
It can be true/false so does that mean it's proposition/mathematical statement?
It is only a noun phrase. There is no verb, so it's not a sentence. It can't be true or false.
"Giraffes that are green"
"Giraffes that are green" is not a sentence, but a noun phrase. It cannot be true or false.
"Giraffes that are green are more expensive than elephants." is a complete sentence. It can be true or false.