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    If I know the graph for f(x), would the graph for f(-x) and f(|x|) be the same, i.e. a reflection in the y axis?

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    f(|x|) is only changed left of the y-axis -- the graph for the values of x that are already positive remains unchanged. Hope this helps.
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    (Original post by jbuck100)
    If I know the graph for f(x), would the graph for f(-x) and f(|x|) be the same, i.e. a reflection in the y axis?

    Thanks
    I don't think they would be the same. The modulus of a graph isnt a reflection in the y axis (or x axis), it's just the absolute value of the number (i.e. positive).

    Consider y=x

    If you had f(-x), then X>0 would become negative and X<0 would become positive.

    If you had f(|x|), then just X<0 would change to become positive, becoming a V shape with the origin being the point of intersection with the x axis.
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    nah, f(-x) is a reflection in the y axis - you flip it all over, whereas f(|x|) is everything on the right of the y axis reflected onto the left, and you 'delete' what would usually be on the left. if that makes sense
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    No, think about where you would plot certain values - such as x=-1. Do they do in the same place?
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    f(-x) is a reflection in the y axis

    f(|x|) is a reflection in the y axis except that it's just the bit on the right "pasting" itself on to the left of the y axis. if you think about it, it's because f(-1) ends up being the same as f(1), f(-4) = f(4) etc so the y values are the same as on the positive side of the y axis

    edit; ok that got answered 5 times quickly
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    good point i think they are the same
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    Aah thank you that's made it so much clearer!




    (Original post by victor_b1992)
    good point i think they are the same
    ..lol
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    but it kinda is
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    f(-x) is / changed to \
    f(lxl) is / change to V
 
 
 

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