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Math Help - algrebraic negative fractions and indices

  1. #1
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    algrebraic negative fractions and indices

    Hi,

    I am struggling to simplify:



    The dot/mark in front of the 4 is meant to be a multiplication sign.

    Any help would be great thanks
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  2. #2
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    Just note that:

    (a\cdot b)^c = a^c \cdot b^c and that x^a + x^b = x^{a+b}

    You should be able to figure it our easily now.
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  3. #3
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    Quote Originally Posted by raphw View Post
    Just note that:

    (a\cdot b)^c = a^c \cdot b^c and that x^a + x^b = x^{a+b}

    You should be able to figure it our easily now.
    I know that  (a^m)^n  = a^m^n

    So on first half of equation I get : 2x^-^(^1^/^4^) ^\cdot ^(^2^)

    Am I heading in the right direction?
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  4. #4
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    Quote Originally Posted by shadowzoe View Post
    So on first half of equation I get : 2x^-^(^1^/^4^) ^\cdot ^(^2^)
    Not quite:
    [2x^(-1/4)]^2 = 2^(1*2)x^(-1/4 * 2) = 4x^(-1/2)
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  5. #5
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    Thanks.

    So then 4x^-^1^/^2 \cdot 4x^3^/^2  = (4x)^1

    Thus Answer = 4x

    Is my thinking correct?
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  6. #6
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    Quote Originally Posted by shadowzoe View Post
    Thus Answer = 4x
    You get a ceegar !!
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  7. #7
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    Quote Originally Posted by Wilmer View Post
    You get a ceegar !!
    Wilmer, can I be a pain?

    If X=2

    I cannot get the first equation to match 4x ... where am I going wrong?
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  8. #8
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    You simply got the answer wrong.

    4x^-^1^/^2 \cdot 4x^3^/^2  \ne (4x)^1

    but:

    4x^-^1^/^2 \cdot 4x^3^/^2  = (4)^2(x)^1 = 16x
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  9. #9
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    Thanks Raphw and Wilmer.

    Yeah I woke up this morning and realised I missed of one of the fours at the end.

    Thanks again
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  10. #10
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    Quote Originally Posted by raphw View Post
    Just note that:

    (a\cdot b)^c = a^c \cdot b^c and that x^a + x^b = x^{a+b}
    This is incorrect. I presume raphw meant to write (x^a)(x^b)= x^{a+b} with a multiplication on the left side, not a sum.

    You should be able to figure it our easily now.
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