1) i presume it is [1.5x]
x → [2 , 8/3)
2) x → (-∞ , 1)
\hspace{-16}\bf{\mathbb{S}}$olve for $\bf{x}$\\\\ $\bf{(1)\;\; \lfloor 1.5 \rfloor x+\lfloor x \rfloor=5}$\\\\ $\bf{(2)\;\; \lfloor x \rfloor+\lfloor 2x \rfloor \leq \sqrt{3}}$
for equation 2, x lies between (-∞,1)
[x]+2[x]≤1.732 (rounding off)
for the equation to satisfy x should be less than one...