Question

S = {positive integers} and subset T = {positive integers divisible by 3}, what is T'?
Answer
{1, 2, 3, 4, 5, …}
{1, 2, 4, 5, 7, 8, …}
{3, 6, 9, 12, …}
{ }

Answer 1

3rd one ?

Answer 2

If I read the character carefully, the question asks for T', which is the complement of the third one.

Answer 3

so im right

Answer 4

Complement means it does not contain anything divisible by three.
The third one contains all integers (in fact natural numbers) divisible by three. Complement means all the rest.
The correct answer is {..-5,-4,-2,-1,1,2,4,5,...}
The given question mistook natural numbers for integers and gave all wrong answers. The closest one is the second one, assuming the question asks for natural numbers.

Answer 5

Sorry, the question is correct, since it asks for positive integers.
So the second answer is the complement of T.
Did you check if the question asks for T or T'?

Answer 6

Yeah so i am correct

Answer 7

Meaning which choice?

Answer 8

3?

Answer 9

3 is correct for T, and 2 is correct for T'. Check the question.

Answer 10

I still dont get it

Answer 11

T union T' is the universal set.
T intersect T' is the null set.
If T contains all positive integers divisible by 3 (=choice 3, 3,6,9,...), then T' contains all positive integers that are NOT divisible by 3 (=choice 2, 1,2,4,5,7,8,...).
So if the question asks for T' (complement of T), the choice 2 is the right answer. Does your teach use T' to mean complement of T? There may be different conventions, but in the context, that's what it should mean.

Answer 12

idk because in all the questions the letter has that ' on top but like at the begging of the question it doesnt but at the end does

Answer 13

Review your notes and confirm that your teacher defines the complement of set T as T'. Some use an overline, but it is difficult to type.

Answer 14

I do flvs

Answer 15

and this is a pretest that will take some assignments of and it doesn't let me read the lesson till i finish this pretest

Answer 16

In that case, take it with confidence that T' means the complement of T.
That also explains why you're not familiar with complements.
It's OK. Everything will become clear when the lesson begins.

Answer 17

In retrospect, you may not want to give a correct answer if it is a pretest. The curriculum may think that you already have extensive knowledge and skip the topic, but I hope they're smart enough NOT to do that.

Answer 18

They do like if you get the questions on that topic right the computer takes the assinment on that topic of

Answer 19

OK, then there's no danger. I was worried because I don't know how they use the pretest information.

Answer 20

yeah there are 100 questions for each module and they ask like 10 questions on 10 topics

Answer 21

You're doing alright. Keep up the good work!

Answer 22

thanks but i still dont get this question .