What is the derivative of ln(x)^e ?

In summary, the derivative of \( \ln(x)^e \) can be found using the chain rule and the properties of logarithms. The function can be rewritten as \( e \cdot \ln(x)^{e-1} \cdot \frac{1}{x} \), resulting in the derivative \( \frac{e \cdot \ln(x)^{e-1}}{x} \).
  • #1
lIllIlIIIl
7
5
Can't figure it out, here's a screenshot with better typography.
1693584661856.png
 
Physics news on Phys.org
  • #2
Is this math homework? or something else?

EDIT: Disregard the following as I thought you were trying to integrate this expression which is very hard to do. I leave the proof to the students of the future.

Code:
Often integral tables can help get an answer but they are acceptable when its a homework assignment. I looked at a few and this integral is not listed. They do show ones where ##ln(x)^n## with n an integer but none with a real number power.

What work have you done to solve this?

One attack that might work is to replace ln(x) with y and ask what is the integral for that and then you could use the function of a function approach to get an answer.
 
Last edited:
  • Like
Likes pinball1970
  • #3
lIllIlIIIl said:
Can't figure it out, here's a screenshot with better typography.
View attachment 331333
I can't imagine where that function came from, but the chain rule is your friend!
 
  • Like
Likes WWGD
  • #4
I moved the thread to the homework forums since this is a homework-type problem.
 
  • Like
Likes berkeman
  • #5
Like PeroK said, try describing your function as a composition of other functions . Then apply the Chain Rule.
 
  • #6
lIllIlIIIl said:
Can't figure it out, here's a screenshot with better typography.
View attachment 331333
Your problem is ambiguous, so isn't clear to me.

Is it ##\ln[x^e]## or is it ##(\ln(x))^e##? IOW, are we raising x to the power e or are we raising ##\ln(x)## to the power e?
 
  • #7
jedishrfu said:
One attack that might work is to replace ln(x) with y and ask what is the integral for that
The problem asks for the derivative, not the integral.
 
  • #8
I guess I’m not the only one with a reading problem.
 

FAQ: What is the derivative of ln(x)^e ?

What is the derivative of ln(x)^e?

The derivative of \( (\ln(x))^e \) with respect to \( x \) is \( e (\ln(x))^{e-1} \cdot \frac{1}{x} \). This is found using the chain rule and the power rule.

How do you apply the chain rule to find the derivative of ln(x)^e?

To apply the chain rule, first recognize that \( (\ln(x))^e \) is a composite function where \( u = \ln(x) \) and the outer function is \( u^e \). The chain rule states that the derivative of a composite function \( f(g(x)) \) is \( f'(g(x)) \cdot g'(x) \). Here, \( f(u) = u^e \) and \( g(x) = \ln(x) \). Thus, the derivative is \( e (\ln(x))^{e-1} \cdot \frac{1}{x} \).

Why is the natural logarithm function involved in the derivative of ln(x)^e?

The natural logarithm function \( \ln(x) \) is involved because it is the base function being raised to the power \( e \). When differentiating \( (\ln(x))^e \), the properties of the natural logarithm and the rules of differentiation for exponential and logarithmic functions are used.

Can you simplify the derivative of ln(x)^e further?

The derivative \( e (\ln(x))^{e-1} \cdot \frac{1}{x} \) is generally considered to be in its simplest form. It clearly shows the application of the chain rule and the power rule. Further simplification is not typically necessary unless additional context or constraints are provided.

What are the common mistakes to avoid when finding the derivative of ln(x)^e?

Common mistakes include forgetting to apply the chain rule, incorrectly differentiating \( \ln(x) \), and misapplying the power rule. It's important to remember that \( \frac{d}{dx}[\ln(x)] = \frac{1}{x} \) and to correctly handle the exponent \( e \) when applying the chain rule.

Back
Top