Math Help Forum: Step Function

  1. #1
    Junior Member wpcp15's Avatar
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    Question Step Function

    I missed a day in class, and I dont understand step function. Could somebody explain it to me.

    Here is one of my problems

    graph the function f(x)=[[x+3]], tell its domain and range
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  3. #2
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    a step function (also known as the greatest integer function) is a function in which any value, be it an integer or something in between, moves to the greatest integer NOT GREATER than the value itself, i.e. if you have 1.9, it would move to 1, if you have -1.3, it would move to -2. So, in your equation, f(x)=[[x+3]] it is going to look like a stairway with each x value corresponding to an integer of y, and your steps are going to be moved up by 3. So the domain will be all real numbers, and the range will be all real integers.
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  4. #3
    Junior Member wpcp15's Avatar
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    Thanks
    but what would you do if it is g(x)=[[x]]+3
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  5. #4
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    The answer is exactly the same as you have been given.
    The domain is the set of real numbers; the range is the set of integers.
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  6. #5
    Junior Member wpcp15's Avatar
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    but how would you graph it
    Don't you have to make a table of values?
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  7. #6
    Global Moderator ThePerfectHacker's Avatar
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    Quote Originally Posted by wpcp15 View Post
    but how would you graph it
    Don't you have to make a table of values?
    It is ugly looking.
    f(x)=[x]+3
    Attached Thumbnails Attached Thumbnails Step Function-picture10.gif  
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