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Homework Help: Reflections of functions

  1. Jul 18, 2011 #1
    1. The problem statement, all variables and given/known data


    Graph f(x) sketch the specified reflection image. State domain/range

    a) the reflection of f(x) = [sqrt]x+2 on the y axis (horizontal shift of 2 to the left)

    2. Relevant equations

    y=[sqrt]x
    3. The attempt at a solution

    I graphed it properly , made a table of values and changed the x values into negetive values since its a reflection on the y axis.

    The graph starts at -2 on the x axis and goes out to the left. -2,0 being the vertex

    It also says state the domain and range. The graph starts at -3 and goes out to the left ( values becoming more and more negetive) I wrote down x < -2 for the domain, but somehow thats wrong. The book says x> -2 .

    http://i51.tinypic.com/xaovom.jpg

    Graph provided, i have messy writing , i know but look at the graph and instruct meo n what to do. I dont get how its Greater than -2, thats not possible..
     
  2. jcsd
  3. Jul 18, 2011 #2

    eumyang

    User Avatar
    Homework Helper

    In your attachment you write that the reflection of y = sqrt(x + 2) is y = sqrt(-x + 2). But you graphed y = sqrt(-x - 2).

    Also, is the book asking for the domain/range for the original function, y = sqrt(x + 2), or its reflection? Because, when you said that according to the book the domain is x > -2, that's the domain of the original function, not the reflection. So either you misread the problem or the book is wrong.
     
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