ĐK: $x\geq 2$Pt $\Leftrightarrow C^x_{x+1}+C^{x-1}_{x+1}=C^{2x-3}_{x+2}$$\Leftrightarrow C^{x}_{x+2}=C^{2x-3}_{x+2}$$\Leftrightarrow x=2x-3\Leftrightarrow x=3$
ĐK: $
2\leq x\
leq
5$Pt $\Leftrightarrow C^x_{x+1}+C^{x-1}_{x+1}=C^{2x-3}_{x+2}$$\Leftrightarrow C^{x}_{x+2}=C^{2x-3}_{x+2}$$\Leftrightarrow x=2x-3\Leftrightarrow x=3$