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    my teacher decided to flippin move me up to further maths next week so I need someone to help me understand this topic cause I'm far behind the rest
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    Answer depends what level this is.

    You can think of the domain as the acceptable inputs and the range the possible outputs of those inputs.

    By acceptable, I mean the element in the domain should map to an element on the rage; the function should be defined for that value.

    E.g. y=1/x

    Domain; x is any real number but 0
    Range; y is any real number but 0

    y=x^2
    Domain: x is any real number
    Range: y>= 0
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    They are part of functions

    Domain are the x values that "map" the y values on graphs. Then range are for the y values that you can possibly have from the x values
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    (Original post by ima.hogg)
    x
    The domain of a function is the complete set of real values that can be inputted into the function for it to give a real output.

    Where as the range of a function is the complete set of possible outputs of the function.

    For example the graph of  y = \sqrt{x - 2}

    Has a domain of x >= 2 because the value within the root cannot be less than 0 or the output wouldn't be a real number.

    And it has a range of y >= 0 because a real value of a square root will never be negative.
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    (Original post by ima.hogg)
    my teacher decided to flippin move me up to further maths next week so I need someone to help me understand this topic cause I'm far behind the rest
    domain is the set of value that you can stick into a function and range is what comes out when you stick the domain into the function

    for example f(x)=x² where f:[0,2]\Rightarrow [0,4] so that domain is 0,2 so all the numbers including 0 and 2 i have defined as valid things you can stick into f(x) and to get the range you stick 0 and 2 into f(x) and see wat comes out in this case it's 0 and 4 so that's the range.

    Or you can think of the domain as the x axis and the range as the y axis

    so if you have the graph x² and the domain is 0 and 2 then you can look at the graph of x² between 0 and 2 and see what corresponding y values 0 and 2 give
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    ahh so if the question asks you to find the domain of f(x)=x², would the domain be all the real numbers because you can put any number into the function?
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    (Original post by ima.hogg)
    ahh so if the question asks you to find the domain of f(x)=x², would the domain be all the real numbers because you can put any number into the function?
    Yes indeed it would! :yep:
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    Thanks a lot everyone!!
    It isn't as hard I thought it would be... or at least I hope so:jumphug:
 
 
 
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