/ | 2|
| x 10 |50 + x |
| -- + --- |-------|
| 15 3*x | x |
| ----------- for --------- < 1
| 2 15
| 50 + x
| 1 - -------
| 15*x
<
| oo
|____
|\ `
| \ n
| \ /x 10\
| / |-- + ---| otherwise
| / \15 3*x/
|/___,
\n = 1
$$\begin{cases} \frac{\frac{x}{15} + \frac{10}{3 x}}{1 - \frac{x^{2} + 50}{15 x}} & \text{for}\: \frac{\left|{\frac{x^{2} + 50}{x}}\right|}{15} < 1 \\\sum_{n=1}^{\infty} \left(\frac{x}{15} + \frac{10}{3 x}\right)^{n} & \text{otherwise} \end{cases}$$
Piecewise(((x/15 + 10/(3*x))/(1 - (50 + x^2)/(15*x)), Abs((50 + x^2)/x)/15 < 1), (Sum((x/15 + 10/(3*x))^n, (n, 1, oo)), True))