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Math Help - Exponents, unlike mulitiplication, do NOT "distribute" over addition.

  1. #1
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    Exponents, unlike mulitiplication, do NOT "distribute" over addition.

    i think this is supposed to be an example of an exponent not "distributing over addition?

    (x-2)2

    (x 2)2 = (x 2)(x 2) = xx 2x 2x + 4 = x2 4x + 4.


    I don't understand where they are getting the -2x from?

    is this question even right?

    someone please help..thanks
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  2. #2
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    basic formula

    (a-b)^2= a^2 - 2*a*b + b^2
    so we got

    (x-2)^2=(x-2)(x-2)= x*x-x*2-2*x-2(-2)=x^2-4x+4

    we are multiplying each terms with others; x with two other terms in other perentecies and than 2 with other terms in other perentecies same as x(x-2)=x^2-2x and ading other term -2(x-2)=-2x+4

    hope this is understandable
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  3. #3
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    Quote Originally Posted by sherlewman View Post
    i think this is supposed to be an example of an exponent not "distributing over addition?

    (x-2)2

    (x 2)2 = (x 2)(x 2) = xx 2x 2x + 4 = x2 4x + 4.

    I don't understand where they are getting the -2x from?

    is this question even right?
    someone please help..thanks
    If you multiply two sums you have to multiply each summand of the first bracket by each summand of the second bracket. Afterwards collect like terms.
    Attached Thumbnails Attached Thumbnails Exponents, unlike mulitiplication, do NOT "distribute" over addition.-distrib_gesetz.png  
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  4. #4
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    understand that!!!!

    thank you for you help...understand you description better....
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