Math 1314
Graph of Logarithmic Functions
Section 4.2 Notes
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Math 1314
Section 4.2 Notes
x
The exponential function y = a and the logarithmic function y = logax are inverse functions. Their graphs
are reflected in the line y = x.
Examples:
1. Graph the function y = log2x. State the domain, the range, and asymptote.
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Math 1314
Section 4.2 Notes
2. Graph the function f(x) = log2(x + 1) by starting from the graph of y = log2x. State the domain, the
range, and asymptote.
y = log2x
f(x) = log2(x + 1)
D:
D:
R:
R:
Asymptote:
Asymptote:
Key points:
Key points:
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Math 1314
Section 4.2 Notes
3. Graph the function f(x) = log3x – 1 by starting from the graph of y = log3x. State the domain, the
range, and asymptote.
y = log3x
f(x) = log3x – 1
D:
D:
R:
R:
Asymptote:
Asymptote:
Key points:
Key points:
4.
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Math 1314
5.
Section 4.2 Notes
Graph the function f(x) = log2 (x – 1) + 2 by starting from the graph of y = log2x. State the
domain, the range, and asymptote.
y = log2x
f(x) = log2 (x – 1) + 2
D:
D:
R:
R:
Asymptote:
Asymptote:
Key points:
Key points:
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Math 1314
6.
Section 4.2 Notes
Graph the function f(x) = 2 – ln x by starting from the graph of y = lnx. State the domain, the
range, and asymptote.
f(x) = 2 – lnx
y = lnx
D:
D:
R:
R:
Asymptote:
Asymptote:
Key points:
Key points:
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