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    This question really confuses me trying to solve it:

    Simplify:

    (0.0001/t^8)^-3/4

    I never get the answer, which is 100t^6.

    Please help, :smartass:
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    (Original post by iPthreefifthteen)
    This question really confuses me trying to solve it:

    Simplify:

    (0.0001/t^8)^-3/4

    I never get the answer, which is 100t^6.

    Please help, :smartass:
    The answer is 1000t^6.

    Represent 0.0001 as a fraction, then you know that x^(-t) = 1/x^t and then indice laws and so on.
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    As said above, the answer is actually 1000t^6. Here's a clue for your working:

    (0.0001/t^8)^-3/4
    = (t^8/0.0001)^3/4
    = (10000*t^8)^3/4
    ... can you do the last 2 steps?
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    (Original post by tomthecool)
    As said above, the answer is actually 1000t^6. Here's a clue for your working:

    (0.0001/t^8)^-3/4
    = (t^8/0.0001)^3/4
    = (10000*t^8)^3/4
    ... can you do the last 2 steps?
    Thank you, Yes it's clear to me know it must be a typo error on the crappy edexcel book.

    I think the last 2 step are:

    1.) t^8 * 3/4 = 8/1 * 3/4 = 24/4 = 6 therefore t^6

    2.) the same step as above didn't work for me i.e 10000/1 * 3/4 = 7500, but instead I found that if I * the power by ^3 and then square root it twice I get a 1000.

    Finally if you times them together you get 1000t^6 , step 2 was a bit unclear for me but I think if I ever come across something similar then I'll just have to stick with that method.
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    (Original post by iPthreefifthteen)
    Thank you, Yes it's clear to me know it must be a typo error on the crappy edexcel book.

    I think the last 2 step are:

    1.) t^8 * 3/4 = 8/1 * 3/4 = 24/4 = 6 therefore t^6

    2.) the same step as above didn't work for me i.e 10000/1 * 3/4 = 7500, but instead I found that if I * the power by ^3 and then square root it twice I get a 1000.

    Finally if you times them together you get 1000t^6 , step 2 was a bit unclear for me but I think if I ever come across something similar then I'll just have to stick with that method.
     x^4 = x.x.x.x

     x^{\frac{1}{4}} = \sqrt[4]{x}
    A number to the power of 3/4 doesn't mean multiply it by 0.75.
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    (Original post by Clarity Incognito)
     x^4 = x.x.x.x

     x^{\frac{1}{4}} = \sqrt[4]{x}
    A number to the power of 3/4 doesn't mean multiply it by 0.75.
    How come it works with t^8, 8/1 * 3/4 = 24/4 = t^6?

    That's the only thing that baffles me.
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    (Original post by iPthreefifthteen)
    How come it works with t^8, 8/1 * 3/4 = 24/4 = t^6?

    That's the only thing that baffles me.
     \sqrt[4]{t^8} = t^2, (t^2)^3 = t^6 following indice laws. It's just a coincidence.
 
 
 
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