SOLUTION: For the exponential function e^x and logarithmic function log x, graphically show the effect if x is doubled, can someone help me with the problem, I do not understand what they ar

Algebra ->  Exponential-and-logarithmic-functions -> SOLUTION: For the exponential function e^x and logarithmic function log x, graphically show the effect if x is doubled, can someone help me with the problem, I do not understand what they ar      Log On


   



Question 172999: For the exponential function e^x and logarithmic function log x, graphically show the effect if x is doubled, can someone help me with the problem, I do not understand what they are asking. Thank you!!!

Found 2 solutions by stanbon, gonzo:
Answer by stanbon(75887) About Me  (Show Source):
You can put this solution on YOUR website!
For the exponential function e^x and logarithmic function log x, graphically show the effect if x is doubled,
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e^x vs. e^(2x)

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ln(x) vs ln(2x)
graph%28400%2C300%2C-5%2C5%2C-5%2C20%2C%2C2.71828%5E%28-x%29%2C2.71828%5E%28-2x%29%29
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Comment:I can't get this site to graph ln(x) and ln(2x) which is ln(x) + ln(2)
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Cheers,
Stan H.

Answer by gonzo(654) About Me  (Show Source):
You can put this solution on YOUR website!
they want to know the impact of doubling x.
i take this to mean:
if you have e%5Ex and you double x, then you have e%5E%282x%29
likewise:
if you have log%2810%2Cx%29 and you double x, then you have log%2810%2C2x%29
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first i will graph e%5Ex and e%5E%282x%29 to see what the impact would be:
look below the graph for further comments.
graph%28800%2C800%2C-3%2C5%2C-2%2C20%2C2.718281828%5Ex%2C2.718281828%5E%282x%29%29
the faster rising curve is e%5E%282x%29
when x = 0, the values of both curves is the same.
when x = 1, the value of e%5Ex is 2.718... and the value of e%5E%282x%29 is 7.389...
when x = 2, the value of e%5Ex is 7.389... and the value of e%5E%282x%29 is 54.598...
the value of e%5E2x appears to be the value of %28e%5Ex%29%5E2 which is should since%28a%5Eb%29%5Ec equals a%5E%28b%2Ac%29 by the laws of exponentiation.
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when x = -.5, e%5Ex = .6065 and e%5E%282x%29 = .3678.
.6065%5E2 = .3678 so the ratio holds even though e%5E%282x%29 is smaller than e%5Ex at this point.
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you can see this on the graph.
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the graph of log%2810%2Cx%29 and log%2810%2C2x%29 is shown now.
look below the graph for further comments.
graph%28800%2C800%2C-2%2C40%2C-1%2C2%2Clog%2810%2Cx%29%2Clog%2810%2C2x%29%29
this graph doesn't show such a dramatic change in the value of log(x) versus log(2x)
example:
when x = 10, log(x) = 1, and log(2x) = 1.301...
when x = 100, log(x) = 2, and log(2x) = 2.301...
when x = 1000, log(x) = 3, and log(2x) = 3.301...
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this is because when x is an exponent, it has a very large impact on the result.
when x is the result of exponentiation, it has a very small impact on the result.
when x is the exponent, this is what happens:
if you take x = 1, then 10^1 = 10
if you take x = 10, then 10^10 = 10000000000
there's a big difference.
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when x is the result of exponentiation, this is what happens:
if you take x = 1000, then 10^y = 1000 which means y = 3.
if you double x to be 2000, then 10^y = 2000 which means y = 3.301029996
doubling the answers causes a very small increase in the exponent.
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y = 10^x means x is the exponent
y = log(x) means x is the answer.
remember:
y = log(x) if and only if x = 10^y
x is the result of exponentiation when you say y = log(x)
x is the exponent itself when you say y = 10^x.
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best i can do.
hope it makes sense.
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