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    So I get most of it, there's just one step that I don't understand. For example:

    -7x2+14x-22

    = -7(x2-2x)-22
    =-7(x2-2x+1-1)-22

    The next bit I don't get. You're supposed to factorise the bit in brackets, excluding the -1, i.e. you're supposed to factorise x2-2x+1 aren't you? But the video I'm watching says it should be (x-1)2, but I don't understand why... Can anyone explain why? Thanks!
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    can you post the video please brother?
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    when 'a' does not equal 1, you find two numbers that multiply to give 'a x c' and add to give 'b' then rewrite the original equations but instead of 'b' you'll write those two values.
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    (Original post by Prokaryotic_crap)
    can you post the video please brother?
    Sure, can only post the mobile address though :P http://m.youtube.com/?#/watch?v=P7txG33JGVc
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    from the:

    -7(x^{2}-2x)-22

    =
    -7(x^{2}-2x+1-1)-22 adding 1, and subtracting it

    =
    -7((x^{2}-2x+1)-1)-22 bracketing the +1 with x^2 and -2x

    =

    -7((x-1)^2-1)-22

    =

    -7(x-1)^2-15

    EDITED)
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    (Original post by Hasufel)
    from the:

    -7(x^{2}-2x)-22

    =
    -7(x^{2}-2x+1-1)-22 adding 1, and subtracting it

    =
    -7((x^{2}-2x+1)-1)-22 bracketing the +1 with x^2 and -2x

    =

    -7((x-2)^2-1)-22

    =

    -7(x-2)^2-15
    Okay, so how did the x^2 -2x +1 become (x-2)^2?
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    at the top, you said (x-1)^2

    if video says (x-2)^2 that`s balls!
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    (Original post by Qaiys)
    Okay, so how did the x^2 -2x +1 become (x-2)^2?
    It doesn't - it should be (x-1)^2
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    (Original post by davros)
    It doesn't - it should be (x-1)^2
    So how does it become that? :P
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    (Original post by Qaiys)
    So I get most of it, there's just one step that I don't understand. For example:

    -7x2+14x-22

    = -7(x2-2x)-22
    =-7(x2-2x+1-1)-22

    The next bit I don't get. You're supposed to factorise the bit in brackets, excluding the -1, i.e. you're supposed to factorise x2-2x+1 aren't you? But the video I'm watching says it should be (x-1)2, but I don't understand why... Can anyone explain why? Thanks!
    If thats what you need factoring..

    ax2 - bx + c = x2 - 2x + 1 = (x-1)2

    When factoring, remember that if it follows the standard form quadratic equation (ax2 + bx + c = 0), then to make things easier for yourself begin with two empty brackets.

    1. ( )( ) We see at this point, upon examining your equation that we have x2 - 2x + 1. As we know, this means simply that x is multiplying by itself. So it follows that:

    2. (x )(x ). To establish what we need next, we should consider the "c" in the standard form, and find what C equals in our equation. In this instance, the number we are looking for is = x2 - 2x + 1. So we take 1, and consider its its factors.. (just 1 lol.) Usually we would examine which pair of factors would combine together to give us "b". (x2- 2x + 1). However in this case, as 1 only has a factor of 1, we neednt bother with that step. So we proceed to fill in the brackets.

    3. (x 1)(x 1). Be sure to leave a space between x and 1 (or whatever future number you insert here). As mentioned earlier, we have to consider that since we know the factors of c (1 in this case) combine to make bx, we know that in some way, somehow, 1 and 1 combine to make -2 (x2- 2x + 1) So we examine in what way our pair of factors combine to make -2, in this case, it's -1 and -1.

    4. (x - 1)(x - 1). So we simply added the - sign between the x and the 1. Had b = +2 in x2+ 2x + 1, then we wouldve used + signs in the brackets instead.

    5 (x - 1)2 . Because (x-1) multiplied by (x-1) is the same as (x-1)2

    At the risk of this post getting marked at a dissertation we'll quickly prove how (x-1)2 = x2 - 2x + 1. We'll use the FOIL method... because it's fresher than tupperware. First Outer Inner Last.

    (x - 1)(x - 1) = x2 First (x times x is x2)
    (x - 1)(x - 1) = x2-1x Outer (x times -1 = -1x)
    (x - 1)(x - 1) = x2 -1x -1x Inner (x times -1 = -1x)
    (x - 1)(x - 1) = x2 -1x -1x +1 Last (-1 times -1 = +1.)

    So would you agree, that by simplifying the above , we get:
    (x - 1)2 = x2 -2x +1

    If so, GOOD JOB MOTHER ****ER CAUSE WE JUST WENT QUADRATIC UP IN THIS *****
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    (Original post by Hasufel)
    from the:

    -7(x^{2}-2x)-22

    =
    -7(x^{2}-2x+1-1)-22 adding 1, and subtracting it

    =
    -7((x^{2}-2x+1)-1)-22 bracketing the +1 with x^2 and -2x

    =

    -7((x-2)^2-1)-22

    =

    -7(x-2)^2-15
    oops

    I think you meant (x-1)
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    (Original post by Qaiys)
    So I get most of it, there's just one step that I don't understand. For example:

    -7x2+14x-22

    = -7(x2-2x)-22
    =-7(x2-2x+1-1)-22

    The next bit I don't get. You're supposed to factorise the bit in brackets, excluding the -1, i.e. you're supposed to factorise x2-2x+1 aren't you? But the video I'm watching says it should be (x-1)2, but I don't understand why... Can anyone explain why? Thanks!
    You appear to be completing the square rather than factorising - what does your question ask?
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    (Original post by Reece Sure)
    If thats what you need factoring..

    ax2 - bx + c = x2 - 2x + 1 = (x-1)2

    When factoring, remember that if it follows the standard form quadratic equation (ax2 + bx + c = 0), then to make things easier for yourself begin with two empty brackets.

    1. ( )( ) We see at this point, upon examining your equation that we have x2 - 2x + 1. As we know, this means simply that x is multiplying by itself. So it follows that:

    2. (x )(x ). To establish what we need next, we should consider the "c" in the standard form, and find what C equals in our equation. In this instance, the number we are looking for is = x2 - 2x + 1. So we take 1, and consider its its factors.. (just 1 lol.) Usually we would examine which pair of factors would combine together to give us "b". (x2- 2x + 1). However in this case, as 1 only has a factor of 1, we neednt bother with that step. So we proceed to fill in the brackets.

    3. (x 1)(x 1). Be sure to leave a space between x and 1 (or whatever future number you insert here). As mentioned earlier, we have to consider that since we know the factors of c (1 in this case) combine to make bx, we know that in some way, somehow, 1 and 1 combine to make -2 (x2- 2x + 1) So we examine in what way our pair of factors combine to make -2, in this case, it's -1 and -1.

    4. (x - 1)(x - 1). So we simply added the - sign between the x and the 1. Had b = +2 in x2+ 2x + 1, then we wouldve used + signs in the brackets instead.

    5 (x - 1)2 . Because (x-1) multiplied by (x-1) is the same as (x-1)2

    At the risk of this post getting marked at a dissertation we'll quickly prove how (x-1)2 = x2 - 2x + 1. We'll use the FOIL method... because it's fresher than tupperware. First Outer Inner Last.

    (x - 1)(x - 1) = x2 First (x times x is x2)
    (x - 1)(x - 1) = x2-1x Outer (x times -1 = -1x)
    (x - 1)(x - 1) = x2 -1x -1x Inner (x times -1 = -1x)
    (x - 1)(x - 1) = x2 -1x -1x +1 Last (-1 times -1 = +1.)

    So would you agree, that by simplifying the above , we get:
    (x - 1)2 = x2 -2x +1

    If so, GOOD JOB MOTHER ****ER CAUSE WE JUST WENT QUADRATIC UP IN THIS *****
    Hahaa thanks a lot!!
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    (Original post by TenOfThem)
    You appear to be completing the square rather than factorising - what does your question ask?
    It was completing the square, I just got a bit confused on the way but I understand now
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    (Original post by TenOfThem)
    oops

    I think you meant (x-1)

    Aaagh! to quote stewie: "*****...i just got jacked, *****!"

    SORTED NOW, THOUGH
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    (Original post by Qaiys)
    Hahaa thanks a lot!!
    No problem. Hope that helped clear things up!
 
 
 
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