Ta có :
\(\frac{x+3}{2003}+\frac{x+2}{2004}+\frac{x+1}{2005}=-3\)
\(\Leftrightarrow\)\(\left(\frac{x+3}{2003}+1\right)\left(\frac{x+2}{2004}+1\right)\left(\frac{x+1}{2005}+1\right)=-3+3\)
\(\Leftrightarrow\)\(\frac{x+2006}{2003}+\frac{x+2006}{2004}+\frac{x+2006}{2005}=0\)
\(\Leftrightarrow\)\(\left(x+2006\right)\left(\frac{1}{2003}+\frac{1}{2004}+\frac{1}{2005}\right)=0\)
Vì \(\frac{1}{2003}+\frac{1}{2004}+\frac{1}{2005}\ne0\)
Nên \(x+2006=0\)
\(\Rightarrow\)\(x=-2006\)
Vậy \(x=-2006\)
Chúc bạn học tốt ~
\(\frac{x+3}{2003}+\frac{x+2}{2004}+\frac{x+1}{2005}=-3\)
\(\left(\frac{x+3}{2003}+1\right)+\left(\frac{x+2}{2004}+1\right)+\left(\frac{x+1}{2005}+1\right)=0\)
\(\frac{x+2006}{2003}+\frac{x+2006}{2004}+\frac{x+2006}{2005}=0\)
\(\left(x+2006\right)\left(\frac{1}{2003}+\frac{1}{2004}+\frac{1}{2005}\right)=0\)
\(x+2006=0\left(Vì\frac{1}{2003}+\frac{1}{2004}+\frac{1}{2005}\ne0\right)\)
\(\Rightarrow x=-2006\)
bài này lớp 5 còn làm đc có điều chưa học số âm
