I am trying an FTC problem.
$$\frac{d}{dx}\int_0^{9\ln x}e^t \,dt=\ ?$$
How do I evaluate $$e^{9\ln(x)(9/x)}$$
EDIT: Ok, I made a mistake above, and put the chain rule result in the exponent!
Wrong! Here is the correct way, using FTC:
$$\huge{\frac{d}{dx}\int_0^{9\ln x}e^t \,dt=(e^{9lnx})\frac{9}{x}=(e^{lnx})^9(\frac{9}{x})=\frac{x^9}{1}\frac{9}{x}=9x^8}$$
I don't understand what you did, but anyway: $$\frac{d}{dx}\int_0^{9\ln x}e^t \,dt=\frac{d}{dx}(e^{9\ln x}-1)=\frac{d}{dx}(x^9-1)=9x^8.$$