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Homework Help: Really basic expanding question: Forgot how!

  1. Sep 12, 2012 #1
    1. The problem statement, all variables and given/known data

    Going through my review material, and I need some help on this simple procedure.

    example 1: (2x + 1)^2

    example 2: 2(x^2 -1)

    I forgot how to do this. Can someone please help me out?

    2. Relevant equations

    3. The attempt at a solution

    Example 1: 2x squared is 4x?.... I dunno. Im stuck. I need a good review on how to do this simple procedure. Any website link to a review/refreasher would be good.

    Thanks guys
  2. jcsd
  3. Sep 12, 2012 #2


    Staff: Mentor

    Ex. 1: What does the exponent 2 indicate?
    Ex. 2: Hint - distributive property.

    Don't you have a textbook?
  4. Sep 12, 2012 #3
    Just have a calculus book. I am doing a review for calc, and I dont have a Math 12 book.

    Ex 1: would it turn into (2x + 1)(2x + 1) ?

    Ex 2: would it be just (2x^2 - 2)????

    Last edited: Sep 12, 2012
  5. Sep 12, 2012 #4


    Staff: Mentor

    1. Yes, but you still need to expand it. There are four multiplications - FOIL (first, outer, inner, last)
    2. Yes.
  6. Sep 13, 2012 #5
    Remember that for #1, each pair of factors needs to be grouped together for multiplication (ie 2x*2x, 2x*1, 1*2x, 1*1). After you're done multiplying, add the like terms: 4x2 (remains the same; no like terms to which it can add), 2x+2x=4x, and 1. Final answer: 4x2+4x+1
  7. Sep 13, 2012 #6


    Staff: Mentor

    You're going to have a very tough time in calculus if you are puzzled about basic algebra concepts. If you can't get the book you studied algebra from, there are lots of decent books out there that you could buy for not much money.
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