# Exponential functions differentiation intro | Advanced derivatives | AP Calculus AB | Khan Academy

### 10 thoughts on “Exponential functions differentiation intro | Advanced derivatives | AP Calculus AB | Khan Academy”

• July 22, 2016 at 8:27 pm

Hi khanacademy,Your videos helped me so much but i have 1 question. Isn't khan academy a non profit organization. You might probably get money for having 2.6 million subs.

• July 24, 2016 at 6:13 am

shouldn't a be a be a positive number greater than zero to make this work? Since you're using ln(a)

• December 26, 2016 at 12:18 pm

sorry I am a little confused, if the derivative of ln(x) is 1/x then why is the derivative of lna just lna? Should it not be 1/a?

• February 15, 2017 at 12:32 pm

Well, I don't understand why (ln(a)*x)' = ln(a),. it's because of e^x'=e^x but just otherwise?

• February 16, 2017 at 12:28 pm

Cute

• November 8, 2017 at 8:01 pm

thank you so much !

• December 28, 2017 at 3:35 pm

I pressed stop at 2.20 becouse it waay over my math. without proof and showing where it comes from Im soo lost already. wrote very negative comment at khan acedemy(turkish version) . It s already hard to grasp first time aaand its english video without proof. -khan.."yea alreaaaht its ln a to something equals this. becouse I said soo o yeaaaa baby"… how where from why? nope no proof (khan logic)maybe we will do an explanation video like trigs derivatives after first we asked hunreds of questions …yes shoot first ask later nice logic keep on KHAN

• April 14, 2018 at 5:02 pm

Wow I wish I learned it this way the first time. This is so sensible. It also is a great demonstration of how e can be used to manipulate unwieldy functions into something manageable for transformations, and then back again. I see results from this type of use of exponential identities all the time, but I haven't seen one so clearly and plainly explained.
Such a great video.
Side note: I was a middle school drop out — stopped learning math in 7th grade. At 31 I went back to school, took a career and life planning class, and learned I could be satisfied as an actuary. But lo, how to get from point a to point b. I couldn't even remember how to add fractions. I spent a summer studying with Khan Academy, working examples along with the videos, then tested into elementary algebra. I'm not sure if I'm able to convey the significance Khan Academy played in my life. Just try to imagine what it would feel like to be a 31 year old with 18 years of failure and fear as your adult identity. I was so alone and so scared, and Khan Academy gave me a lifeline.
Anyway, now I'm in one of the top actuarial sciences program in the united states, I just finished a quarter with deans honors and I just passed the P/1 actuarial exam.

Khan Academy helps to keep the American Dream alive, and that's a fact. Thank you all for what you do. Spread my story if you feel inclined. It's real and it's significant.