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    Hi,

    I've been reading through the CGP GCSE book after a long spell out from mathematics and I've covered numbers and algebra so far. It's been going well but I am struggling to understand this particular proof example.

    (n+3)²- (n-2)² n² + 6n + 9 - (n² -4n + 4).

    Where do 6n and 4n come from?

    Thanks for your help

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    AlgeBRUH

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    (Original post by Wdolidol19)
    Hi,

    I've been reading through the CGP GCSE book after a long spell out from mathematics and I've covered numbers and algebra so far. It's been going well but I am struggling to understand this particular proof example.

    (n+3)²- (n-2)² n² + 6n + 9 - (n² -4n + 4).

    Where do 6n and 4n come from?

    Thanks for your help

    They come from multiplying 2 brackets together

    What do you think you get from (x+3)(x+3)
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    You don't square each term individually. Look at it as (n+3)(n+3) - (n-2)(n-2).
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    (Original post by Wdolidol19)
    Hi,

    I've been reading through the CGP GCSE book after a long spell out from mathematics and I've covered numbers and algebra so far. It's been going well but I am struggling to understand this particular proof example.

    (n+3)²- (n-2)² n² + 6n + 9 - (n² -4n + 4).

    Where do 6n and 4n come from?

    Thanks for your help

    It basically means to expand the brackets out so, it would look like this (n+3)(n+3) multiply them and the same goes to the second bracket
 
 
 
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