# X have mass function For what values of α is it the case that E(X^α)

LetXhave mass function $ f(x) = \left\{ \begin{array}{l l} \{x(x+1)\}^{-1} & \quad \text{if x = 1, 2, ...,}\\ 0 & \quad \text{otherwise,} \end{array} \right $ and let α∈R. For what values of α is it the case that E(X^α)<∞ ? Can u please help I am dumbstruck from where to start

```
α<1/2
```

```
α<1
```

```
α>1
```

`α<3/4`

Add Comment