Prove 1-n^2>0, Then 3n-2 is Even | Math Homework Help

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In summary: It is not a homework problem in the usual sense, but it is a "how do I do this" problem.In summary, the conversation is about proving that for any integer n, if 1-n^2>0, then 3n-2 is an even integer. The solution involves setting n=0 and showing that 3n-2 is -2, which is an even integer. The questioner is asking for help with wording their solution correctly.
  • #1
bonfire09
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Homework Statement



Let nεZ,Prove that 1-n^2>0, then 3n-2 is an even integer.

Homework Equations


The Attempt at a Solution



I proved it like this. I think its right but I am not able to word it correctly.

Since 1-n^2>0 therefore n=0. Then 3n-6=3(0)-6=-6. Since 0 is an integer, 3n-6 is even.

How can I learn to word this correctly because I am having some trouble with it?
 
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  • #2
Try posting in the number theory forum, this isn't really calculus.
 
  • #3
this is intro to proofs actually. I am trying to self study.
 
  • #5
I wouldn't worry too much about proper wording as long as you get the concept. n has to equal zero and -6 is an even integer...sounds proved to me. :)

Although, you probably shouldn't take my advice. I'm shunned by many in academia due to my deep detestation of pretentiousness. ;)
 
  • #6
bonfire09 said:

Homework Statement



Let nεZ,Prove that 1-n^2>0, then 3n-2 is an even integer.
The above is confusing. A better statement would be
Let n ##\in## Z. If 1 - n2 > 0, then show that 3n - 2 is an even integer.
bonfire09 said:

The Attempt at a Solution



I proved it like this. I think its right but I am not able to word it correctly.

Since 1-n^2>0 therefore n=0. Then 3n-6=3(0)-6=-6. Since 0 is an integer, 3n-6 is even.

How can I learn to word this correctly because I am having some trouble with it?
Note that you have a typo in your work. You're supposed to prove that 3n - 2 is an even integer.

I would say it like this:
Since 1 - n2 > 0 and n ##\in## Z, then n = 0.
So 3n - 2 = - 2, which is an even integer.

Therefore, for any integer n, if 1 - n2 > 0, then 3n - 2 is an even integer.

Whovian said:
Try posting in the number theory forum, this isn't really calculus.
It should NOT be posted in the number theory section. That section and the other sections under Mathematics are not for homework and homework-type problems

Whovian said:
No, here is probably fine, although the Precalc Mathematics section would also be a good choice.
 

Related to Prove 1-n^2>0, Then 3n-2 is Even | Math Homework Help

1. How do you prove 1-n^2 > 0?

In order to prove that 1-n^2 > 0, we can use the fact that n^2 is always greater than or equal to 0. This means that when we subtract n^2 from 1, the result will always be greater than 0.

2. What does it mean for 3n-2 to be even?

A number is considered even if it is divisible by 2 without leaving a remainder. In the case of 3n-2, this means that the value of the expression will always be a multiple of 2.

3. How do you prove that 3n-2 is even?

In order to prove that 3n-2 is even, we can use the fact that any integer multiplied by an even number will always result in an even number. Since 3 is an odd number, the remaining number in the expression (n-2) must be even for the whole expression to be even. And since n-2 is even, this means that 3n-2 is also even.

4. Can you use a counterexample to disprove the statement?

No, we cannot use a counterexample to disprove the statement. The statement is a conditional statement which means that it is true for all possible values of n. A counterexample would only disprove the statement if it is not true for all values of n, but in this case, the statement is true for all values of n.

5. How does the initial statement relate to the evenness of 3n-2?

The initial statement, 1-n^2 > 0, serves as a premise or condition for proving that 3n-2 is even. By showing that 1-n^2 is always greater than 0, we can then use this information to prove that 3n-2 is always even.

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