Would this have been marked correct?

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The discussion centers on whether a student's expanded expression, 2df + 2f2 - 2de - 2e2, would be marked correct in an exam compared to the book's answer, -2e2 + 2f2 - 2de + 2df. Participants agree that the student's answer is valid and would likely receive full credit, emphasizing that the order of terms does not affect the correctness due to the commutative property of addition. Some caution is noted regarding exceptions in higher-level mathematics, such as vector multiplication. Overall, the consensus is that the student's answer is acceptable and reflects a proper understanding of the material. The discussion concludes with reassurance about the student's approach to the problem.
Gringo123
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I had to expand the brackets in this expression:
2f[d+e+f]-2e[d+e+f]

My answer is:
2df + 2f2 -2de - 2e2

The answer in my book is the same but all the components are in different places:
-2e2 +2f2 -2de + 2df

Would my answer have been ok in an exam?
 
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Yes, definitely!

If you would have had any marks deducted, your teacher has issues.
 
Mentallic is right but it doesn't follow in every case but looking at your standard (may be class II) it is always right for you. In higher classes you will find something different. Like in vector multiplication A x B is not equal to B x A. similarly you'll find that A + B is not equal to B + A. But don't worry about it today.
 
Thanks a lot folks!
 

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