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

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Homework Help Overview

The discussion revolves around understanding the behavior of logarithmic functions and their transformations, particularly focusing on the shifts of asymptotes and discrepancies in graph points compared to a graphing calculator's output.

Discussion Character

  • Exploratory, Assumption checking, Problem interpretation

Approaches and Questions Raised

  • Participants explore the transformations of the logarithmic function, questioning the shifts in asymptotes and the resulting graph points. There is a focus on understanding the effects of compressions, expansions, reflections, and translations on the graph.

Discussion Status

Some participants have offered insights into the transformations involved, noting the importance of factoring and the implications of the function's domain. Others are attempting to clarify their understanding and re-evaluate their graphs based on the feedback received.

Contextual Notes

There is a mention of specific points and their discrepancies between the original graph and the graphing calculator's output. The discussion also highlights the need to consider the domain restrictions of the logarithmic function in question.

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.
 
Last edited by a moderator:
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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
 
Last edited:
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
 
Last edited by a moderator:

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