venialove said:
f(x)= ln ? (x^2+1) divided by x(2x^3-1)^2
= ln x + 2 (2x divided by x^2+ 1) - 1/2 ln ( 2x^3-1)
f''(x)= 1/x +2 ( 2x divided by x^2+ 1) minus 1/2 (6x^2 divided by 2x^3-1)
your problem:
find f'(x) when
\(\displaystyle f(x)\, = \, ln\frac{\sqrt{x^2 \, + \, \, 1}}{x \cdot (2x^3-1)^2}\)
\(\displaystyle f(x)\, = \, \frac{1}{2}\cdot ln[x^2 \, + \, \, 1] \, - ln[x] \, - \, 2\cdot ln(2x^3-1)\)
\(\displaystyle f'(x)\, = \, \frac{1}{2}\cdot \frac{1}{x^2 \, + \, \, 1}\cdot [2x] \, - \frac{1}{[x]} \, - \, 2\cdot \frac{1}{2x^3-1}\cdot (6x^2)\)
Now simplify and finish.....
or something else?