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

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Discussion Overview

The discussion centers around proving the equation e^[ln(a)*b] = a^b, exploring intuitive proofs and connections to known properties of exponents and logarithms. Participants share their understanding and seek clarification on the relationship between exponential and logarithmic functions.

Discussion Character

  • Exploratory
  • Technical explanation
  • Conceptual clarification

Main Points Raised

  • One participant expresses understanding of e^ln(x) = x but struggles to justify the proof for e^[ln(a)*b] = a^b, seeking intuitive connections to exponent properties.
  • Another participant suggests that the relationship makes sense through the definition of ln(x) and exp(x) as inverse operations, comparing it to the identity sin(arcsin(x)) = x.
  • A different participant recalls a problem involving simplification to y = (1/2) e^[(ln(10/5))*t] and connects it to the property x^(ab) = (x^a)^b, indicating a moment of realization about the application of logarithmic and exponential rules.
  • One participant notes that ln(a)*b can be observed as ln(a^b), leading to the conclusion that e^(ln(a^b)) simplifies to a^b, although they express some uncertainty about the manipulation of the exponent.

Areas of Agreement / Disagreement

Participants do not reach a consensus on a definitive proof but share various perspectives and insights into the relationship between logarithmic and exponential functions. The discussion remains exploratory with multiple viewpoints presented.

Contextual Notes

Some participants mention psychological barriers when applying multiple rules, indicating potential limitations in their understanding or comfort with the concepts involved. There is also a reliance on properties of logarithms and exponents that may not be universally agreed upon.

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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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