Can you please explain
We have made a mistake.
In step 3, 4, 5 in the image you have posted, derivative of log x is 1/x. From the 4th step, the solution is correct.
We will change the answer soon.
Thank you for finding out mistakes and helping teachoo become better :)
Teachoo is free. Login to view more pages.
Login with facebook
Login with gmail
On signing up you are confirming that you have read and agree to
Terms of Service