1
------------
2
1 + (x - 5)
$$\frac{1}{\left(x - 5\right)^{2} + 1}$$
-2*(-5 + x)
----------------
2
/ 2\
\1 + (-5 + x) /
$$- \frac{2 \left(x - 5\right)}{\left(\left(x - 5\right)^{2} + 1\right)^{2}}$$
/ 2 \
| 4*(-5 + x) |
2*|-1 + -------------|
| 2|
\ 1 + (-5 + x) /
----------------------
2
/ 2\
\1 + (-5 + x) /
$$\frac{2 \cdot \left(\frac{4 \left(x - 5\right)^{2}}{\left(x - 5\right)^{2} + 1} - 1\right)}{\left(\left(x - 5\right)^{2} + 1\right)^{2}}$$