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Math Help - brackets within brackets

  1. #1
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    brackets within brackets

    hi how would I work out the following?
    (3(2^2 -2)^2 -10)^2

    which brackets do I calculate first please?
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  2. #2
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    Quote Originally Posted by wolfhound View Post
    hi how would I work out the following?
    (3(2^2 -2)^2 -10)^2

    which brackets do I calculate first please?
    Start with the innermost and move outwards:

    1. 2^2-2 = {\color{red}2}
    2. {\color{red}2}^2 = {\color{blue}4}
    3. 3 \times {\color{blue}4} = {\color{green}12}
    4. {\color{green}12} - 10 = 2
    5. 2^2 = 4
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  3. #3
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  4. #4
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    You can also use google calculator to check your answer. Paste the problem into google and hit search

    http://www.google.com/#hl=en&source=hp&q=%283%282^2+-2%29^2+-10%29^2&aq=f&aqi=&oq=&fp=e705e53e3f505592
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  5. #5
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    value of x

    find value of x if x-2 =5x + 14
    more helps please

    I havent learned how to do these yet I just want to find out how and then I will catch on
    Thanks
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  6. #6
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    Quote Originally Posted by wolfhound View Post
    find value of x if x-2 =5x + 14
    more helps please

    I havent learned how to do these yet I just want to find out how and then I will catch on
    Thanks

    HI

    x-2=5x+14

    x-5x=14+2

     <br />
-4x=16<br />

     <br />
x=-4 <br />
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  7. #7
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    Quote Originally Posted by mathaddict View Post
    HI

    x-2=5x+14

    x-5x=14+2

     <br />
-4x=16<br />

     <br />
x=-4 <br />
    cool thanks
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  8. #8
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    another find x

    How about this one
    find value of x if
    2x-1/x+2 = 3

    and
    is 5 a solution of x^2 + 3x-9=(x-4)(x+21)??
    If so please explain how I do it
    Thanks!!!!!
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  9. #9
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    actually is x =7 the first one...
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  10. #10
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    Quote Originally Posted by wolfhound View Post
    How about this one
    find value of x if
    2x-1/x+2 = 3

    and
    is 5 a solution of x^2 + 3x-9=(x-4)(x+21)??
    If so please explain how I do it
    Thanks!!!!!
    HI again .

    If you need any more help , its better to start a new thread . Well , i am going to answer this . If you have any more q's , start a new onw

    \frac{2x-1}{x+2}=3

    2x-1=3(x+2)

    2x-1=3x+6

    x=-7


     <br />
x^2+3x-9=(x-4)(x+21)<br />

    x^2+3x-9=x^2+17x-84

    3x-9=17x-84

    14x=75

    x=75/14

    So 5 is not a solution .
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  11. #11
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    Quote Originally Posted by mathaddict View Post
    HI again .

    If you need any more help , its better to start a new thread . Well , i am going to answer this . If you have any more q's , start a new onw

    \frac{2x-1}{x+2}=3

    2x-1=3(x+2)

    2x-1=3x+6

    x=-7


     <br />
x^2+3x-9=(x-4)(x+21)<br />

    x^2+3x-9=x^2+17x-84

    3x-9=17x-84

    14x=75

    x=75/14

    So 5 is not a solution .
    Thanks so much for your help I will start a new thread when I have more questions...
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  12. #12
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    e^(i*pi)'s Avatar
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    You seem to have the wrong sign for both of them

    \frac{2(7)-1}{7+2} = \frac{13}{9} \neq 3

    by inspection x = -7

    -----------------

    For the 2nd one 31 \neq 26 so 5 is not a solution

    x^2+3x-9 = x^2+17x-84

    -14x = - 75
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