Bài 4:
a: ĐKXĐ: \(x\notin\left\{1;-1\right\}\)
b: \(M=\dfrac{x}{2x-2}+\dfrac{x^2+1}{2-2x^2}\)
\(=\dfrac{x}{2\left(x-1\right)}-\dfrac{x^2+1}{2\left(x-1\right)\left(x+1\right)}\)
\(=\dfrac{x^2+x-x^2-1}{2\left(x-1\right)\left(x+1\right)}=\dfrac{1}{2\left(x+1\right)}\)
c: Để M=1/2 thì 2(x+1)=2
=>x+1=1
hay x=0