Prove e^ln(a)*b = a^b: Intuitive Proof

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SUMMARY

The discussion centers on proving the identity e^[ln(a)*b] = a^b. The participant initially struggles with the intuitive understanding of this equation but realizes that it stems from the properties of logarithms and exponentials being inverse functions. The proof is established by recognizing that e^(ln(a)) = a, leading to the conclusion that (e^ln(a))^b = a^b. This understanding is reinforced by the properties of exponents, specifically that x^(ab) = (x^a)^b.

PREREQUISITES
  • Understanding of exponential functions and their properties
  • Familiarity with logarithmic functions, specifically natural logarithms (ln)
  • Knowledge of the relationship between logarithms and exponentials as inverse operations
  • Basic algebraic manipulation of exponents
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  • Study the properties of logarithms, focusing on natural logarithms and their applications
  • Explore the concept of inverse functions in mathematics, particularly between exponential and logarithmic functions
  • Learn about the laws of exponents and how they apply to simplifying expressions
  • Investigate further proofs involving logarithmic identities and their implications in calculus
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Students of mathematics, educators teaching algebra and calculus, and anyone seeking to deepen their understanding of logarithmic and exponential relationships.

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Prove e^[ln(a)*b] = a^b

I understand perfectly why e^ln(x) = x ... and ...I see why it works numerically but I can't justify it in terms of proof? I'd be satisfied if I could dilute this into some other proofs I'm familiar with like exponent properties such as c^(a+b) = (c^a)*(c^b) but I can't seem to figure it out intuitively.. searching the internet hasn't yielded a desired answer either.

Edit: Nvm... e^(ab) = (e^a)^b so then (e^ln(a))^b = a^b
 
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It will make sense only in terms of the definition of ln(x) and exp(x) being inverse operations.

Intuition with inverse operations and functions is a bit different from what you may be used to.

It's more like (sin(arcsin(x)) = x
 
Yea I was doing a problem that had gotten simplified down to y = (1/2) e^[(ln(10/5))*t] and couldn't figure out how they got to y= (1/2)*10^(t/5) but then I remembered x^(ab) = (x^a)^b... ln and exp make intuitive sense to me since log base e of e... I just hit a psychological blocker since I had to apply too many rules at once.
 
Start observing that ## \left(\ln{a}\right)\cdot b=\ln{a^{b}}##...
 
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Ssnow said:
Start observing that ## \left(\ln{a}\right)\cdot b=\ln{a^{b}}##...
Well the exponent has to stay inside the ln function so you end up with e^(ln(a^b)) but then I suppose a^b would drop down, so yea that would work too.
 

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