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    (Original post by SeanFM)
    As long as you see the point I am trying to illustrate. Eg domain (for real values of x) of
    Unparseable or potentially dangerous latex formula. Error 6: Image was not produced or one of its dimensions is too small.
    \sqrtx
    = ..

    Go away, potentially dangerous latex message! :hand:
    Its not showing it
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    (Original post by Ayaz789)
    Its not showing it
    I am a disaster with latex I have fixed it now but it is on the other page.. it was \sqrt x.
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    (Original post by SeanFM)
    I am a disaster with latex I have fixed it now but it is on the other page.. it was \sqrt x.
    What about the root of x?
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    (Original post by Ayaz789)
    What about the root of x?
    The domain of y=\sqrt x in the reals is..
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    (Original post by SeanFM)
    The domain of y=\sqrt x in the reals is..
    Im sorry but i dont understand what you are saying do you mean [1,infinity)
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    (Original post by Ayaz789)
    Im sorry but i dont understand what you are saying do you mean [1,infinity)
    I am asking you to find the range of values that you can put into that equation (i.e, the domain) and express it in terms of [] or (] or whatever the correct parentheses are.
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    (Original post by SeanFM)
    I am asking you to find the range of values that you can put into that equation (i.e, the domain) and express it in terms of [] or (] or whatever the correct parentheses are.
    Is it not [1, infinity) though?
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    (Original post by Ayaz789)
    Is it not [1, infinity) though?
    the infinity is a can of worms once more.. perhaps I should have not picked that. But 1 is not the right value. (Eg sqrt0.25 = 0.5 which exists).
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    (Original post by SeanFM)
    the infinity is a can of worms once more.. perhaps I should have not picked that. But 1 is not the right value. (Eg sqrt0.25 = 0.5 which exists).
    Yeah i know that but just stay with whole numbers for now, i thought infinity is always a curved bracket?
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    (Original post by Ayaz789)
    Yeah i know that but just stay with whole numbers for now, i thought infinity is always a curved bracket?
    That's not how it works - you can't exactly 'stay with the whole numbers' - if the function exists for x=0.25 for example then that's going to be part of your domain.

    And I do not know.. I have never studied such things I guess it makes sense though.
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    (Original post by SeanFM)
    That's not how it works - you can't exactly 'stay with the whole numbers' - if the function exists for x=0.25 for example then that's going to be part of your domain.

    And I do not know.. I have never studied such things I guess it makes sense though.
    just saying infinity is always a curved bracket ahh okay nw! Anyways im going sleep so ill message you tomorrow
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    (Original post by SeanFM)
    And I do not know.. I have never studied such things I guess it makes sense though.
    The reason that you always use the curved brackets is because []/() notation is shorthand for [a, b] being \{x \in \mathbb{R} : a \leq x \leq b\}.

    But a problem comes up when you trying b=\infty because then you require x=b \in \mathbb{R} but infinity is not a member of the reals, so you can't say x=b, i.e: it can't be inclusive. It has to exclude \infty with a a \leq x < \infty. i.e: the curved bracket.
 
 
 
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