Let the random variable $\text{X}$ has a mixed distributions with probability $\text{P(X = 0)} = \alpha,$ and the density function.
$f_{x}(x) = \left\{\begin{matrix} \beta x^{2} (1 – x), 0 < x < 1& \\ 0, \text{otherwise}& \end{matrix}\right.$
If the expectation of $\text{X}$ is $\alpha,$ then the value of $4 \alpha + \beta$ is equal to :
- $9/2$
- $6$
- $9$
- $5/2$