How do I simplify n(n+1)/2 + n+1?

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Discussion Overview

The discussion revolves around the simplification of the expression n(n+1)/2 + n+1. Participants explore methods to simplify this expression and compare it with another expression, n(n+1)(2n+6)/6 + (n+1)^2, aiming to derive a common form.

Discussion Character

  • Mathematical reasoning
  • Homework-related

Main Points Raised

  • One participant expresses difficulty in simplifying the expression n(n+1)/2 + n+1 and mentions a derived form (n+1)(n+2)/2.
  • Another participant suggests expanding parentheses as a method to simplify and equate the original problem with the derived answer.
  • A participant attempts to simplify the expression but arrives at an incorrect result, n^4 + 1/2, which does not match the expected form.
  • Another participant points out that the division by 2 only applies to (n^2 + n) and encourages further expansion of the expressions.
  • A later reply indicates that the participant has understood the simplification process after receiving guidance.

Areas of Agreement / Disagreement

Participants do not reach a consensus on the simplification process, as there are differing approaches and some confusion regarding the steps involved.

Contextual Notes

There are unresolved steps in the simplification process, and participants express varying levels of understanding regarding the application of mathematical operations.

helpm3pl3ase
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I can't seem to figure out how to simplify this!

n(n+1)/2 + n+1

which they were able to get (n+1)(n+2)/2 by simplifying that

and this

n(n+1)(2n+6)/6 + (n+1)^2

and they were able to get (n+1)(n+1+1)(2(n+1)+1)/6 out of this one.

Any help is greatly appreciated.
 
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Try this: surely you know how to "expand" parenthesis, like this: a(b+c) ---> ab + ac.

So do this both from the given problem expression, and also from the answer. Like this:
Problem -----> xxx
Answer ------> xxx
And try to get the same "xxx" starting from both ends.

When you have that, you can walk *forward* the steps from the problem, and then *backward* the steps from the solution:
Problem ------> xxx -------> Answer.
 
ok i did that but for the first one i get

(n^2 + n)/2 + n + 1

=

n^2 + n + n + 1/2

= n^4 + 1/2

but this does not equal (n+1)(n+2)/2
 
You have only expanded the parenthesis on the initial problem... but have not expanded them yet on the solution. Try expanding (n+1)(n+2)/2.

And hey! Watch out, the /2 is dividing (n^2 + n), and only those two. Try again the first part.
 
Last edited:
ooo I see I got it.. Thanks for the help!
 

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