Hii there dear student!

Firstly, Is the log natural log or log with base 10, and also log(y/a), is it in power of 'a' or multiplied with the square of 'a'.

Please revert to this and then I can help you with the exact solution of the question.

The general method to find out the point of inflexion is:-

1. Find out the first derivative of the curve provided
2. And then the second derivative in the same way
3. Equate the second derivative equal to zero, and accordingly find out the values of y and then x by putting it in the main equation.

Hope this helps!

Best wishes.