u
ĐK: \(x\ne\pm7\)
PT trở thành:
\(\dfrac{3\left(x+7\right)}{x^2-49}+\dfrac{2\left(x-7\right)}{x^2-49}=\dfrac{5}{x^2-49}\\ \Leftrightarrow3x+21+2x-14-5=0\\ \Leftrightarrow5x=-2\\ \Leftrightarrow x=-\dfrac{2}{5}\left(TM\right)\)
v
ĐK: \(x\ne1;x\ne0\)
PT trở thành:
\(\dfrac{\left(x+1\right)x}{x\left(x-1\right)}-\dfrac{3x+1}{x\left(x-1\right)}=\dfrac{\left(x-1\right)}{x\left(x-1\right)}\\ \Leftrightarrow x^2+x-3x-1-x+1=0\\ \Leftrightarrow x^2-3x=0\\ \Leftrightarrow x\left(x-3\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\left(loại\right)\\x=3\left(TM\right)\end{matrix}\right.\)
r
ĐK: \(x\ne2\)
PT trở thành:
\(\dfrac{\left(5+x\right).2}{3\left(x-2\right).2}-\dfrac{\left(2x-3\right).3}{2\left(x-2\right).3}=\dfrac{1}{2}\\ \Leftrightarrow10+2x-6x+9-\dfrac{1}{2}=0\\ \Leftrightarrow-4x=-\dfrac{37}{2}\\ \Leftrightarrow x=\dfrac{37}{8}\left(TM\right)\)
s
ĐK: \(x\ne0;x\ne2\)
PT trở thành:
\(\dfrac{6x-x^2}{x\left(x-2\right)}+\dfrac{x.x}{\left(x-2\right).x}=\dfrac{3\left(x-2\right)}{x\left(x-2\right)}\\ \Leftrightarrow6x-x^2+x^2-3x+6=0\\ \Leftrightarrow3x=-6\\ \Leftrightarrow x=-2\left(TM\right)\)
x
ĐK: \(x\ne2;x\ne0\)
PT trở thành:
\(\dfrac{\left(x+2\right).x}{\left(x-2\right).x}-\dfrac{\left(x-2\right)}{x\left(x-2\right)}=\dfrac{2}{x\left(x-2\right)}\\ \Leftrightarrow x^2+2x-x+2-2=0\\ \Leftrightarrow x^2+x=0\\ \Leftrightarrow x\left(x+1\right)=0\\ \Leftrightarrow\left[{}\begin{matrix}x=0\left(loại\right)\\x=-1\left(TM\right)\end{matrix}\right.\)
