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    Determine the elements of the following set
    A:= {x ϵ Q | x^4 = 1/16}?
    A:= {x ϵ R | x^2= 4 and x ≤ 0}?
    A := {x ϵ R | x^2= 1 and 4x 1=0}?
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    If x^4 is 1/16, then x is (+or-) 1/2. Because 1/2 x 1/2 x 1/2 x 1/2 = 1/16 also -1/2 x -1/2 x -1/2 x -1/2 = 1/16
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    ok but then I'm confused with these question
    A:= {x ϵ R | x^2= 4 and x ≤ 0}?
    A := {x ϵ R | x^2= 1 and 4x +1=0}
    they're confusing and since I couldn't find anything related
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    (Original post by ddsizebra)
    ok but then I'm confused with these question
    A:= {x ϵ R | x^2= 4 and x ≤ 0}?
    A := {x ϵ R | x^2= 1 and 4x +1=0}
    they're confusing and since I couldn't find anything related
    Ok if x^2 is 4 , your possible awnsers are either 2 or -2. But it states x is less that or equal to zero so x has to be -2.

    And for the second one 4x + 1 = 0 and x^2=1 there are no solutions to that equation. Are u sure u copied it correct?

    4x+1 = 0 so simply x = -1/4

    and x^2=1 so x =(+-) 1

    Is that what your asking?
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    for the first question I had the same but the 2nd one I was confused. And yes it was copied correctly
    But there was a hint " If a set X consists of elements x,y and z, write your answer in the form X={x,y,z}, whereas as if a set X is empty, write X = Ø. Please explain".
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    (Original post by ddsizebra)
    for the first question I had the same but the 2nd one I was confused. And yes it was copied correctly
    But there was a hint " If a set X comsists of elements x,y and z, write your answer in the form X={x,y,z}, whereas as if a set X is empty, wrote X = Ø. Please explain".
    So since there if there are no solutions such that x \in \mathbb{R}, x^2=1 and 4x+1=0, then the set is......?
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    That's what I'm stuck on and I have no examples with similar questions to these (not even textbooks) so I am stuck
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    (Original post by ddsizebra)
    That's what I'm stuck on and I have no examples with similar questions to these (not even textbooks) so I am stuck
    OK but I'm trying to say that it's really obvious because a set that has no solutions to its conditions is considered to be empty, so the last example is equal to the empty set.
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    how would you explain that there was no sets mathematically for the last question because my answer seems to basic and vague?
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    (Original post by ddsizebra)
    how would you explain that there was no sets mathematically for the last question because my answer seems to basic and vague?
    What do you mean by "no sets"?

    The question asks to describe the elements of each sets, so for the last one there are no elements since \not\exists x \in \mathbb{R} s.t. x^2=1 and 4x+1=0. It's nothing complicated if that's what you expect the answer to be...
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    Sorry some of your text is coded

    " there are no elements since \not\exists x \in \mathbb{R} s.t. x^2=1 and 4x+1=0."
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    thankyou both for helping me!!!!!!
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    (Original post by ddsizebra)
    Sorry some of your text is coded

    " there are no elements since \not\exists x \in \mathbb{R} s.t. x^2=1 and 4x+1=0."
    \not\exists just doesnt come out as good in LaTex but it's just \exists symbol with a line through it, saying that there doesn't exist an x \in \mathbb{R}...
 
 
 
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