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# Is (m-n) equivalent to (n-m)?

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1. So this is a halfway solution by TeeEm on arthimetic sequence [Question 124]
And I was wondering if (m-n) equivalent to (n-m)?

I've also noticed that 2 was changed to -2 so aren't you supposed to change (m+n) to (-n-m) ??

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So this is a halfway solution by TeeEm on arthimetic sequence [Question 124]
And I was wondering if (m-n) equivalent to (n-m)?

I've also noticed that 2 was changed to -2 so aren't you supposed to change (m+n) to (-n-m) ??

It goes from 2(m-n)(m+n) to -2(m+n)(n-m). Notice the minus sign in the front.
So this is a halfway solution by TeeEm on arthimetic sequence [Question 124]
And I was wondering if (m-n) equivalent to (n-m)?

I've also noticed that 2 was changed to -2 so aren't you supposed to change (m+n) to (-n-m) ??

Yes, that's right because he essentially took a factor of -1 out of (m-n) and put it on the outside of the bracket. All of the terms are being multiplied together so the expressions are equivalent, but written differently.
4. (m-n) = -(n-m)

if m+n was changed to -n-m then it would cancel out with the -2
5. (Original post by rayquaza17)
It goes from 2(m-n)(m+n) to -2(m+n)(n-m). Notice the minus sign in the front.
(Original post by pineneedles)
Yes, that's right because he essentially took a factor of -1 out of (m-n) and put it on the outside of the bracket. All of the terms are being multiplied together so the expressions are equivalent, but written differently.
Oh I see !! Thank you!!
6. (Original post by qsom)
(m-n) = -(n-m)

if m+n was changed to -n-m then it would cancel out with the -2
Great!! Thank you!!

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