Suppose a real-valued function class $\mathcal{F}$ with pseudo dimension less than $d$, I am wondering what is the pseudo dimension of the following function class \begin{equation} \mathcal{F}_2 = \{\min(f_1, f_2), \text{with } f_1,f_2\in \mathcal{F}\} \end{equation} where for any $x$, $\min(f_1, f_2)(x) = \min(f_1(x), f_2(x))$. My intuition tells me that the pseudo dimension of $\mathcal{F}_2$ should be bounded by $2d$, but I just cannot prove it.
Any help is appreciated!