Need help to solve a quick silly question..
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I know we use natural log...but i forgot how to apply the natural log derivative
I need a hint plz
Where did you learn that you're supposed to use natural log to find the derivative of this?
I remember that since the base isn’t a variable, you apply the natural log to the base and then apply the chain rule... that’s as far as i can remember
What you're supposed to do is let \(u = 2x + 1\). Then take the derivative of \(e^u\) with respect to \(u\) and take the derivative of \(2x + 1\) with respect to x using the chain rule. There's no natural log involved in this.
K so the question is to find the relative maxima and relative minima.... and i was suppose to find the first derivative of that expression and do a first derivative test to see where the graph changes from positive to negative and vice versa..
All you have to do is just apply the chain rule here. The only reason the derivative of \(e^x\) is \(e^x\) is because the \(x\) is treated as the "outside" function and the derivative of \(x\) is just 1. And then \(1 \cdot e^x\) is just \(e^x\). So with \(e^{2x+1}\) it's the same way. \(2x + 1\) is treated as the outside function and the derivative of \(2x + 1\) is just 2. So then multiply two by the inside function \(e^{2x+1}\)
Bro...it’s not e^2x+1 ...
I don't know why I saw the three as an e
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I glanced at it too fast
I even said...the base is an integer... lol
I was already convinced it was e by the time you posted that
Jajajajaja
Shall we proceed to solve the question master? :)
The derivative of \(a^x\) is \(a^x \ln(a)\)
Wait, let me draw
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Hang on, \(e\) IS involved in this
Yikes..
Apparently, you're supposed to use the exponent rule \(a^b = e^{b \ln(a)}\) before applying the derivative
Wat? I was gonna use the log laws for some reason....you know, bring the 2x+1 to the front thingy
You're supposed to find the derivative of 2x + 1 when you do that
The answer you have is already correct. Just remove the \(x\) from the \(2x\)
Wait one second... let me draw
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Sorry, that was a silly mistake.
Correct
So what rule/equation do i use to find the derivative??? Plz let me know to avoid confusion
Showing it to you would probably confuse you
I guarantee it's in Larson's Calculus
Nope, it’s from my college textbook...
Literally they threw in this random expression out of nowhere... while before that i solved like 11 functions that had nothing to do with this kinda question..
I meant the derivative rule is in the Larson Calculus textbook.
Can you tell me tho :/ i need to include in my notes so i know what rule to apply the next time i study math again...next year
You could find it in the textbook faster than I could explain it
It's not exactly a simple to explain rule
Aww... then how will i be able to remember what to do the next time i study this course with an empty mind??
"next time you study this course". There's gonna be a next time? Why would you do that do yourself?
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After that, i can just apply the power rule and collect terms
The DERIVATIVE of a^x is a ln(a)
You can't just post a^x is a^x ln(a) without proper context
SMH, I'm making mistakes trying to cover your mistakes
That was frustrating to see
Khekhekhekhe
The derivative of a^x is a^xln(a)
That only works if it's just \(x\) in the exponent though
Let me see something though.
K so the context is that whenever i see a base as an integer, i take the ln of the base, then apply power rule and rearrange the terms ...
Okay, so I did a little research and there's an alternative way to find the derivative that gives an equivalent result. (Equivalent meaning the result will look different but the expressions are still identical)
Here it is: To find the derivative of \(3^{2x+1}\) Let's say the expression is \(a^{bx + c}\) We re-write it as \(a^{bx} \cdot a^{c}\) Then \(a^c\) is a constant and we can apply the constant rule \((cf)' = cf'\) In other words \(\boxed{(a^{bx} \cdot a^c)' = a^c(a^{bx})' = a^c [a^{bx} \ln(a) \times b]}\)
There's your rule
I see ... will i be able to apply the first derivative test on that tho ? Cuz i need to find where the expression is a relative maxima or a relative minima
Yes
I see now... k thanks mate. Really appreciated your help :)
Check your dm now lol
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