SOLUTION: {{{ -log( 3,x ) +2 }}} I have figured out that the +2 is not (x+2) but -log(3x)+2. I know that the x-intercept for this logarithm is (9,0) and that this log graphs in Quadrant I

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: {{{ -log( 3,x ) +2 }}} I have figured out that the +2 is not (x+2) but -log(3x)+2. I know that the x-intercept for this logarithm is (9,0) and that this log graphs in Quadrant I      Log On


   



Question 446668: +-log%28+3%2Cx+%29+%2B2+
I have figured out that the +2 is not (x+2) but -log(3x)+2. I know that the x-intercept for this logarithm is (9,0) and that this log graphs in Quadrant I with a vertical asymptote being the y-axis. The graph crosses into quadrant IV through point (9,0).
I am suppose to convert and plot this logarithm as an exponent. Then using the X,Y points I devise, invert and use to plot the logarithm.
I am not able to convert to an exponent as I do not know how to handle the +2. I can't seem to reverse engineer this using the points (9,0) either as the negative sign prevents this.
I'm pretty stuck. I would really love some kind of hints to solving this one.
Thank you so much for your time and expertise!!

Found 2 solutions by stanbon, scott8148:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
y = -log(3x)+2
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graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C-%28ln%283x%29%2Fln%2810%29%29%2B2%29
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Determine the inverse:
1st: Interchange x and y.
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x = -log(3y)+2
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2nd: Solve for "y":
-log(3y) = x-2
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log(3y) = 2-x
---
3y = 10^(2-x)
y = (1/3)*10^(2-x)
graph%28400%2C300%2C-10%2C10%2C-10%2C10%2C%281%2F3%2910%5E%282-x%29%29
---
That is the inverse function.
3rd: Graph both on the same set of axes:

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Cheers,
Stan H.

Answer by scott8148(6628) About Me  (Show Source):
You can put this solution on YOUR website!
y = +-log%28+3%2Cx+%29+%2B+log%283%2C9%29+

y = +log%283%2C9%29+-+log%28+3%2Cx+%29+

y = +log%283%2C%289%2Fx%29%29+

3^y = 9/x