2. (10 points) Let $a \triangle b$ and $a \nabla b$ represent taking the minimum and maximum of two numbers $a$ and $b$, respectively. For example, $3 \triangle 4=3, 3 \nabla 4=4$. For different numbers $x$, the number of possible values for $5 \nabla[4 \nabla(x \triangle 4)]$ is $\qquad$.
【Analysis】Discuss in two cases: $x>4$ and $x \leqslant 4$, and solve accordingly.
【Solution】Solution: Discuss in cases:
(1) When $x \leqslant 4$, $x \triangle 4=x, 4 \nabla x=4,5 \nabla 4=5$;
(2) When $x>4$, $x \triangle 4=4,4 \nabla 4=4,5 \nabla 4=5$.

Therefore, the value of $5 \nabla[4 \nabla(x \triangle 4)]$ has 1 possibility.
The answer is: 1.