\(\frac{x-1}{13}+\frac{x-2}{14}+\frac{x-3}{15}+3=0\)
\(\frac{x-1}{13}+1+\frac{x-2}{14}+1+\frac{x-3}{15}+1=0\)
\(\frac{x-1}{13}+\frac{13}{13}+\frac{x-2}{14}+\frac{14}{14}+\frac{x-3}{15}+\frac{15}{15}=0\)
\(\frac{x+12}{13}+\frac{x+12}{14}+\frac{x+12}{15}=0\)
\(\left(x+12\right)\left(\frac{1}{13}+\frac{1}{14}+\frac{1}{15}\right)=0\)
\(x+12=0\)hay \(\frac{1}{13}+\frac{1}{14}+\frac{1}{15}=0\)(vô lý)
=>x+12=0
x=0-12
x=-12
Vậy x=-12
\(\frac{x-1}{13}\)+ \(\frac{x-2}{14}\) + \(\frac{x-3}{15}\)+ 3 = 0
=> (\(\frac{x-1}{13}\)+ 1 ) + (\(\frac{x-2}{14}\)+ 1) + (\(\frac{x-3}{15}\) + 1) = 0
=> \(\frac{x+12}{13}\)+ \(\frac{x+12}{14}\)+ \(\frac{x+12}{15}\)= 0
=> (x + 12) . (\(\frac{1}{13}\)+\(\frac{1}{14}\)+ \(\frac{1}{15}\)) = 0
=>(x + 12) . \(\frac{587}{2730}\)= 0
=> x + 12 = 0
=> x = -12
Vậy x = -12
