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Subtracting integers with powers

  1. Nov 4, 2008 #1
    1. The problem statement, all variables and given/known data
    Hey, sorry about this. Its really obvious, i think there's just some really simple way to do it. Its annoying me, my teacher couldnt do it either!

    Evaluate 6667²-3333² (without a calculator)

    2. Relevant equations

    3. The attempt at a solution

    I know there is just some really obvious way to do it. It was only worth 2 marks. Checking the answer on a calculator it was 33340000 and 6667-3333=3334 so i wasnt sure if that was how you did it, found the answer to the integers minus each other and add zeros. But i tried other examples and it didnt hold true.

  2. jcsd
  3. Nov 4, 2008 #2


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    At some point in class, you should have covered what the difference of two squares is. Just to remind you, it looks something like this:

    I hope that helps.
  4. Nov 4, 2008 #3


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    You in general can also try to factorize the terms and calculate and simplify that way; but in the example you gave, knowing the difference of two squares is more efficient as in post #2.
  5. Nov 4, 2008 #4
    Awesome, cheers guys!
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