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Nelo
Jul18-11, 04:26 PM
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..

eumyang
Jul18-11, 05:04 PM
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.