\(\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}=\frac{x+1}{13}+\frac{x+1}{14}\)
\(\Rightarrow\frac{x+1}{10}+\frac{x+1}{11}+\frac{x+1}{12}-\frac{x+1}{13}-\frac{x+1}{14}=0\)
\(\Rightarrow\left(x+1\right).\left(\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\right)=0\)
mà 1/10 > 1/13; 1/11>1/14
\(\Rightarrow\frac{1}{10}+\frac{1}{11}+\frac{1}{12}-\frac{1}{13}-\frac{1}{14}\ne0\)
=> x + 1 = 0
x = -1
x+110+x+111+x+112=x+113+x+114x+110+x+111+x+112=x+113+x+114
⇒x+110+x+111+x+112−x+113−x+114=0⇒x+110+x+111+x+112−x+113−x+114=0
⇒(x+1).(110+111+112−113−114)=0⇒(x+1).(110+111+112−113−114)=0
mà 1/10 > 1/13; 1/11>1/14
⇒110+111+112−113−114≠0⇒110+111+112−113−114≠0
=> x + 1 = 0
x = -1
