Note that 8 - x and x - 8 only differ by signs, in other words
they are opposites of each other. In that case, you can factor a
-1 out of one of those factors and rewrite it with opposite signs, as shown
in line 3 above.
To find the value(s) needed to be excluded from the domain, we need
to ask ourselves, what value(s) of x would
cause our denominator to be 0?
Looking at the denominator x + 1, I would
say it would have to be x = -1. Don't
you agree?
-1 would be our excluded value. |