Needing some help with Discrete

[Alex K]

Thats the definition of P:the set of all the subsets. Its size is thus the number of subsets.

Anyways, you're welcome

---

That's just whack. I changed my mind. I no longer want to go back to college and relearn all my math again.

Don't be too hard on yourself, this is horribly confusing

---

Fun fact about P: if you stick an infinite set in, you get again an infinite set, but with a larger infinity than the first.

---

Hmm i just find it strange it was asking for the amount of elements and the answer is actually the subsets present. Thank you Alex! I may have more questions to post if only my teacher broke it down like that..

---

Ok here's another one i've no clue where to start as it wasn't covered in class:

2.1.43. Find the truth set of each of these predicates where the domain is the set of integers.

P(x): x2 < 3
Q(x): x2 > x
c) R(x): 2x + 1 = 0

What's x2 suppposed to be?

---

I think you're simply supposed to give all the integer values for x such that these inequalities hold...

So for the last it's the empty set {} cause theres no integer where twice itself gives -1

If by x2 you mean x squared, well, -1 squared is smaller 3, 0 squared is smaller, 1 squared is smaller, and that's it. So the first set is {-1,0,1} i guess...