Derivative of l n ( 𝑥 )
Let's work some practice problems taking the derivative of the natural log,
Note that problems involving this particular derivative essentially always require the Chain Rule, so this is good additional Chain Rule practice too.
Matheno Essentials: Derivative of
Applying the Chain rule, we have
You'll usually see this written as
Practice Problem #1
Differentiate 𝑓 ( 𝑥 ) = l n ( 𝑥 2 + 3 𝑥 − 1 ) .
Practice Problem #2
Differentiate 𝑓 ( 𝑥 ) = √ l n 𝑥 2 .
Practice Problem #3
Differentiate 𝑓 ( 𝑥 ) = l n ( l n 𝑥 ) .
Practice Problem #4
Differentiate 𝑓 ( 𝑥 ) = l n ( 𝑥 2 𝑒 𝑥 ) .
Practice Problem #5
Differentiate 𝑓 ( 𝑥 ) = l n ( c o s 𝑥 5 𝑥 ) .
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