How to derive y = lncos (1 / x)?

How to derive y = lncos (1 / x)?

As shown in the picture

Is college advanced mathematics the same as college advanced mathematics

It's not the same,
First of all, the syllabus is different. It is not required for junior college students to be able to use it, but for undergraduates to understand certain concepts and master some proof methods
And the textbooks are also different, cover page or textbook description will introduce the use of textbooks for junior college or undergraduate
Moreover, the concept of College narrative is often from the perspective of easy to understand image, and many of the concepts of college are special mathematical language, obscure, but very rigorous, the purpose is to prove

f(x)=ln(x-1)-k(x-1)+1
1 K = 1, f (x) max?
2 F (x) has no zero point, find the range of K
When I take the derivative of F (x), the upper derivative of (1,2) is greater than 0, but Max
How to consider zero point

1 K = 1, f (x) max?
Domain: x > 1
f(x)=ln(x-1) -x+2
The stationary point of F '(x) = 1 / (x-1) - 1 = 0 is x = 2
There are: x0;
x>1+1/k f'(x)1.

Find the second derivative, y = ln [f (x)], find y ''

y=ln[f(x)]
y'=f'(x)/f(x)
y''={f''(x)f(x)-[f'(x)]^2}/[f(x)]^2