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  1. #1
    Junior Member eah1010's Avatar
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    Unhappy help

    (-27)^4/3



    No Clue!
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  2. #2
    Senior Member
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    (-27)^4/3 = 81

    Think of it as (-27)^4; then cube root that result.

    So (-27)^4 = 531441; 531441^(1/3) = 81
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  3. #3
    Forum Admin topsquark's Avatar
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    Quote Originally Posted by AfterShock View Post
    (-27)^4/3 = 81

    Think of it as (-27)^4; then cube root that result.

    So (-27)^4 = 531441; 531441^(1/3) = 81
    Or: [(-27)^(1/3)]^4 = [-3]^4 = 81 which doesn't require a calculator.

    The basic rules here are that
    x^(ab) = [(x^a)]^b = [(x^b)]^a

    and

    x^(1/b) = the "b"th root of x. ie. x^(1/2) = sqrt(x), x^(1/3) = cube root (x), etc.

    -Dan
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