just like in numerical fractions, form a common denominator, which is this case is
(x+h+8)(x+8)
Also your use of square brackets suggest that you have a typo and you forgot the /h at the end,
which is the usual form of this fraction
I will insert it for you
[(8)/(x+h+8)] - [(8)/(x+8)]/h
= [ (8(x+8) - 8(x+h+8) )/((x+h+8)(x+8))]/h
= [(8x+64 - 8x - 8h - 64)/((x+h+8)(x+8) ]/h
= -8h/(h(x+h+8)(x+8))
= -8/((x+h+8)(x+8))
Usually at this point you would take the Limit of that expression as h ---> 0
and you would get
-8/(x+8)^2
How would I subtract this?
[(8)/(x+h+8)] - [(8)/(x+8)]
2 answers
I'm sorry I had to pester you with a problem like that, but my algebra is extremely weak. I understand it now though. Thank you very much! :)