Question

(x+1)^2-4分之x-1,2-4x+2x^2分之1-x通分

Answer 1

(x-1)/[(x+1)^2-4]

=(x+1)/(x+1+2)(x+1-2)

=(x+1)/(x+3)(x-1)

=2(x+1)/2(x+3)(x-1)

(1-x)/(2-4x+2x^2)

=-(x-1)/2(x-1)^2

=-1/2(x-1)

=-(x+3)/2(x+3)(x-1)