Question

x-1分之1+1+x分之1 a²-1分之a+a²-1分之3a+1+1-a²分之2a+3

Answer 1

(1) 1/(x-1)+1/(1+x)

=2x/(x^2-1)

(2) a/(a²-1)+(3a+1)/(a²-1)+(2a+3)/(1-a²)

=(a+3a+1-2a-3)/(a^2-1)

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

=2/(a+1)

(3) (x²-16 )/(8-2x)

=-(x+4)(x-4)/[2(x-4)]

=-(x+4)/2

=-(-2+4)/2

=-1