2b-2/2b^2-8 (find domain to rational expression)

Answer 1

I bet you meant:
(2b - 2)/(2b^2 - 8)
= 2(b-1)/(2(b^2- 4))
= (b-1)/((b+2)(b-2))

domain, any real value of b, b ≠ ± 2

range: any real value

see:
graph of y = (x-1)/(x^2 - 4)

http://www.wolframalpha.com/input/?i=y+%3D+%28x-1%29%2F%28x%5E2+-+4%29+from+-5+to+5

notice the two verticals are the asymptotes and should be dotted lines