Write a definition for the set {1,4,9,16,25,...}
I have two choices: {n^2 | n∈N} and {n | √(n)∈N+}.

if you test whether 3 is an element of the set, do you plug 3 in for n?

Question

Write a definition for the set {1,4,9,16,25,...}
I have two choices: {n^2 | n∈N} and {n | √(n)∈N+}.

if you test whether 3 is an element of the set, do you plug 3 in for n?

inkyvoyd · Answer

essentially, yes.

inkyvoyd · Answer

it is better to use the second definition of the set imo

anonymous · Answer

the first choice seems to be true no matter what n you put in.
The second choice seems to involve a bit more work

inkyvoyd · Answer

well for the first choice you have to actually find a natural number n such that n^2=3

inkyvoyd · Answer

you don't really plug in 3 for n. you plug in 3 for whatever is to the left of the set builder notation. so for the first choice you would plug in 3 for n squared because n^2 is to the left, for the second you would simply plug in n.

anonymous · Answer

thank you :)