Why is the asymptote shifted and points don't match?

AI Thread Summary
The discussion centers on the confusion regarding the shifting of asymptotes and discrepancies in graph points when comparing personal graphs to those generated by a graphing calculator. The asymptote is identified as being shifted 6 units left instead of the expected 3 units due to the transformation of the logarithmic function. Participants clarify that the function's domain is affected by the translation and that the correct approach involves factoring the equation properly. After addressing these issues, the user successfully adjusts their graph. The conversation highlights the importance of understanding function transformations in graphing.
Matt1234
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Here is what the graph looks like on a graphing calculator (notice the equation at the top):

http://img62.imageshack.us/img62/8898/graphingcalc.jpg


Here is what my graph looks like:

http://img53.imageshack.us/img53/7475/lastscanc.jpg

I don't understand why the asymptote is shifted 6 units left instead of 3 units left, And the point on my graph don't seem quite right.

i have the points (-1, -3)
Yet the graphing calculator has (-1, -3.79)

Note : where i wrote original points I am referring to y = log x


I don't see what i hsve done wrong, can someone help me.

Thanks.
 
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Your first step should have taken care of the compressions/expansions, so you should have looked at y = 2ln(1/2*x) first. The 1/2*x inside the parentheses causes an expansion away from the vertical axis. After that, take care of reflections, and finally translations.
 
thanks will try that
 
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Notice that y = -2log(.5x + 3) + 3 = -2log(.5(x + 6)) - 3. This means that
1. The domain of this function is {x | x > -6}
2. The graph of y = -2log(.5x) has been translated to the left by 6 units, and down by 3 units.
 
You hit the nail on the head my friend, I forgot to factor Stupid me!
 
ill try again and post back my result
 
Got it thank you very much, forgot to factor.

Here it is:
http://img62.imageshack.us/img62/2599/lastscanjy.jpg
 
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