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    (Original post by RichE)
    No it isn't. There are rules for which operations to do first and you need to use brackets if you want operations to be done in a different order.
    Its called the reciprocal, to get rid of a negative power you do 1 over the term with the positive power,
    2x^-3 = 1/2x^3
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    Here is my go at it.
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    (Original post by HiggsBoson)
    Its called the reciprocal, to get rid of a negative power you do 1 over the term with the positive power,
    2x^-3 = 1/2x^3
    You're still wrong.

    2x^-3 means 2/(x^3).

    1/2x^3 means (1/2) (x^3)

    To get what you want you should write

    1/(2x^3) or (2x^3)^(-1).

    Look up BIDMAS if necessary. This is pre-GCSE stuff.
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    (Original post by HiggsBoson)
    Its called the reciprocal, to get rid of a negative power you do 1 over the term with the positive power,
    2x^-3 = 1/2x^3
    Pretty sure that would be 2/x^3
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    (Original post by RichE)
    You're still wrong.

    2x^-3 means 2/(x^3).

    1/2x^3 means (1/2) (x^3)

    To get what you want you should write

    1/(2x^3) or (2x^3)^(-1).

    Look up BIDMAS if necessary. This is pre-GCSE stuff.
    OK, I understand the confusion with 1/2x^3, but 2x^-3 mean 2x to the power 3, I don't see any reason to be confused with this.
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    (Original post by The Night King)
    Pretty sure that would be 2/x^3
    lol your right
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    (Original post by HiggsBoson)
    OK, I understand the confusion with 1/2x^3, but 2x^-3 mean 2x to the power 3, I don't see any reason to be confused with this.
    Did you mean to write that?

    And if you meant to write "2x to the power -3" what do you mean by that

    (2x)^(-3) or 2/x^3

    as they are different things?
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    (Original post by RichE)
    Did you mean to write that?

    And if you meant to write "2x to the power -3" what do you mean by that

    (2x)^(-3) or 2/x^3

    as they are different things?
    They equal each other though, 2/x^3 is just simplified.
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    (Original post by HiggsBoson)
    They equal each other though, 2/x^3 is just simplified.
    No they aren't equal - you need to remember your power rules

    (2x)^(-3) = 2^(-3) * x^(-3) = (1/8) x^(-3)
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    (Original post by RichE)
    No they aren't equal - you need to remember your power rules

    (2x)^(-3) = 2^(-3) * x^(-3) = (1/8) x^(-3)
    Oh Ok i get what you mean
 
 
 

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