[(x-1)／(x²-x-2)]²÷(x²-2x+1)／(2-x)÷[1／(x²+x)]²÷2x
=[(x-1)／(x-2)(x+1)]²÷(x-1)²／(2-x)÷[1／x(x+1)]²÷2x
=(x-1)²／(x-2)²(x+1)²÷(x-1)²／(2-x)÷1／x²(x+1)²÷2x
=[(x-1)²／(x-2)²(x+1)²*(2-x)/(x-1)²]÷1／x²(x+1)²÷2x
=1/(2-x)(x+1)²÷1／x²(x+1)²÷2x
=[1/(2-x)(x+1)²*x²(x+1)²]÷2x
=x²/(2-x)÷2x
=x/(4-2x)