Question
Consider two logarithmic functions: f(x)=log3 x
and g(x)=log1/3 x
Determine the coordinates (x,y)
of the point where f(x)
and g(x)
intersect.
and g(x)=log1/3 x
Determine the coordinates (x,y)
of the point where f(x)
and g(x)
intersect.
Answers
GPT-4o mini
To determine the coordinates of the point where the two logarithmic functions \( f(x) = \log_3 x \) and \( g(x) = \log_{\frac{1}{3}} x \) intersect, we need to set them equal to each other:
\[
\log_3 x = \log_{\frac{1}{3}} x
\]
We can use the change of base formula to express \( g(x) \) in terms of base 3:
\[
g(x) = \log_{\frac{1}{3}} x = \frac{\log_3 x}{\log_3 \frac{1}{3}}
\]
Since \( \frac{1}{3} = 3^{-1} \), we have:
\[
\log_3 \frac{1}{3} = -1
\]
Thus, we can rewrite \( g(x) \):
\[
g(x) = \frac{\log_3 x}{-1} = -\log_3 x
\]
Now, substituting this back into the intersection equation:
\[
\log_3 x = -\log_3 x
\]
Adding \( \log_3 x \) to both sides gives:
\[
2\log_3 x = 0
\]
Dividing both sides by 2:
\[
\log_3 x = 0
\]
This means:
\[
x = 3^0 = 1
\]
Now, let's find the corresponding \( y \) value by substituting \( x = 1 \) into either function. We can use \( f(x) \):
\[
f(1) = \log_3 1 = 0
\]
Thus, the coordinates of the intersection point are:
\[
(x, y) = (1, 0)
\]
In conclusion, the point where \( f(x) \) and \( g(x) \) intersect is:
\[
\boxed{(1, 0)}
\]
\[
\log_3 x = \log_{\frac{1}{3}} x
\]
We can use the change of base formula to express \( g(x) \) in terms of base 3:
\[
g(x) = \log_{\frac{1}{3}} x = \frac{\log_3 x}{\log_3 \frac{1}{3}}
\]
Since \( \frac{1}{3} = 3^{-1} \), we have:
\[
\log_3 \frac{1}{3} = -1
\]
Thus, we can rewrite \( g(x) \):
\[
g(x) = \frac{\log_3 x}{-1} = -\log_3 x
\]
Now, substituting this back into the intersection equation:
\[
\log_3 x = -\log_3 x
\]
Adding \( \log_3 x \) to both sides gives:
\[
2\log_3 x = 0
\]
Dividing both sides by 2:
\[
\log_3 x = 0
\]
This means:
\[
x = 3^0 = 1
\]
Now, let's find the corresponding \( y \) value by substituting \( x = 1 \) into either function. We can use \( f(x) \):
\[
f(1) = \log_3 1 = 0
\]
Thus, the coordinates of the intersection point are:
\[
(x, y) = (1, 0)
\]
In conclusion, the point where \( f(x) \) and \( g(x) \) intersect is:
\[
\boxed{(1, 0)}
\]