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    Hiya,

    Having trouble with C3 questions on Domain . Already tried searching for an answer, but found nothing that makes any sense.

    I understand Range means relative to the y-axis and Domain to the x-axis.

    Take for example:

    http://www.imagebam.com/image/56658d64230728

    I know how to show what the inverse function is, but I have no idea how you get the domain as -1 ≤ x ≤ 3.

    Please help !
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    You must first find the range for the first function. 1+ 2sinx so the highest y value is 3 and the lowest is -1. And because the "arc" graphs are inverse, the domain for one is the range of the other and vice versa.
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    You should recall that the domain of f^{-1}(x) is the same as the range of f(x).
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    (Original post by i_hate_examz)
    Hiya,

    Having trouble with C3 questions on Domain . Already tried searching for an answer, but found nothing that makes any sense.

    I understand Range means relative to the y-axis and Domain to the x-axis.

    Take for example:

    http://www.imagebam.com/image/56658d64230728

    I know how to show what the inverse function is, but I have no idea how you get the domain as -1 ≤ x ≤ 3.

    Please help !

    -1/2pi≤sin^-1(x-1/2)≤ 1/2pi

    sin(-1/2pi)≤(x-1/2)≤sin(1/2pi)

    -1≤(x-1/2)≤1
    -2≤x-1≤2
    -1≤x≤3 -----> the domain you wanted.
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    Domain of the inverse function is the range of the normal function.

    Range of normal function is that x is greater than/equal to -1, and less than/ equal to 3, as max of sin is 1, and min of sin is -1.

    Using these values gives you your answer
    • Thread Starter
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    Ah... got it

    Thanks !
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    would the range of the f(x) therefore give the domain of f-1(x)???

    by the way does this only apply for sine graphs or can it be used for linear lines aswel
 
 
 
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