Understanding Logarithmic Identities in Differential Equations

AI Thread Summary
The discussion focuses on the application of logarithmic identities in solving differential equations, specifically how to manipulate the equation 1/8 ln(y) = t + c into the form y = ce^(8t). Participants clarify that multiplying both sides by 8 and exponentiating leads to the exponent of 8. There is a humorous exchange about the difficulty of remembering logarithmic identities, with suggestions of unconventional ways to memorize them, such as tattoos. The conversation highlights the common struggle students face with these mathematical concepts, emphasizing the importance of understanding the underlying identities. Overall, the thread combines educational content with light-hearted banter about exam pressures.
HeLiXe
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This is related to differential equations, but I think my question has more to do with log identities than DE.

I keep seeing equations like

1/8 lny = t + c

simplified to get the solution

y = ce^8t

but I am unsure of the identity being used to get 1/8 into the exponent as 8. I already understand how everything else is simplified, just not this part. Thanks!
 
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Just multiply both sides by 8 and exponentiate both sides.

The other way to see this would be that 1/8 ln(y) = ln(y^{{1}\over{8}})
 
*facepalm* Thanks penguwino LOL
 
That'll be $5
 
I'll give you $25 :-p

I kept switching it over the entire semester and never understood why I was doing that loll. This is what happens when the "simple steps" are skipped in math -_-
 
Tattoo the logarithmic identities to your forearm. It's far more useful then some rose or star
 
^ But then to avoid being suspected of cheating, you'd have to wear full-sleeve shirts during your exams. And that sucks when your exams are seated outside during a heatwave :(
 
Pengwuino said:
Tattoo the logarithmic identities to your forearm. It's far more useful then some rose or star
I'll see if I can have them burned on my retina :D
Dr. Seafood said:
And that sucks when your exams are seated outside during a heatwave :(
That is so sadistic! -_- Who would ever do such a thing to an innocent student?
 
HeLiXe said:
I'll see if I can have them burned on my retina :D

Try to burn them behind your retinas.
That works even better! ;)


HeLiXe said:
That is so sadistic! -_- Who would ever do such a thing to an innocent student?

Oh, standard trick to flush out not-so-innocent students.
 
  • #10
I like Serena said:
Try to burn them behind your retinas.
That works even better! ;)

If there was something behind my retinae it would work better :-p
 
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