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Math Help - Help with rationality proof

  1. #1
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    Help with rationality proof

    Hello all, i could use some help with a problem i cant quite figure out how to prove. I'll keep trying, but any help in the meantime would be greatly appreciated.

    "If x^4 is irrational, then x is irrational" ...Prove true for all Real #'s.


    Is the converse true for all Real #'s x ? (If x is irrational, then x^4 is irrational)


    Thank you,

    Kyle
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  2. #2
    Behold, the power of SARDINES!
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    Quote Originally Posted by CSkyle View Post
    Hello all, i could use some help with a problem i cant quite figure out how to prove. I'll keep trying, but any help in the meantime would be greatly appreciated.

    "If x^4 is irrational, then x is irrational" ...Prove true for all Real #'s.


    Is the converse true for all Real #'s x ? (If x is irrational, then x^4 is irrational)


    Thank you,

    Kyle

    Try proof by contraposition

    not Q implies not P

    if x is rational then x^4 is rational.

    This should be easier.

    the second is not try \sqrt2
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  3. #3
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    nice, thats way easier. thanks empty.
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