SOLUTION: Graph f(x) = log3x

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Question 173131: Graph f(x) = log3x
Answer by jim_thompson5910(35256) About Me  (Show Source):
You can put this solution on YOUR website!
In order to graph f%28x%29=log%283%2C%28x%29%29, we need to plot some points:


Note: I'll use "y" in place of f(x)


Let's find the y value when x=1


y=log%283%2C%28x%29%29 Start with the given equation


y=log%283%2C%281%29%29 Plug in x=1


y=0 Use a calculator to evaluate log base 3 of 1 to get 0


So when x=1, then y=0


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Let's find the y value when x=2


y=log%283%2C%28x%29%29 Start with the given equation


y=log%283%2C%282%29%29 Plug in x=2


y=0.63093 Use a calculator to evaluate log base 3 of 2 to get 0.63093


So when x=2, then y=0.63093


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Let's find the y value when x=3


y=log%283%2C%28x%29%29 Start with the given equation


y=log%283%2C%283%29%29 Plug in x=3


y=1 Use a calculator to evaluate log base 3 of 3 to get 1


So when x=3, then y=1


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Let's find the y value when x=4


y=log%283%2C%28x%29%29 Start with the given equation


y=log%283%2C%284%29%29 Plug in x=4


y=1.26186 Use a calculator to evaluate log base 3 of 4 to get 1.26186


So when x=4, then y=1.26186


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Let's find the y value when x=5


y=log%283%2C%28x%29%29 Start with the given equation


y=log%283%2C%285%29%29 Plug in x=5


y=1.26186 Use a calculator to evaluate log base 3 of 5 to get 1.46497


So when x=5, then y=1.46497


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So we have the following values:


xy
10
20.63093
31
41.26186
51.46497




Now let's plot these points





Now draw a curve through those points to graph f%28x%29=log%283%2C%28x%29%29