Hello Professor Todd,

According to what you said in the earlier email, the horizontal limit is
basically when x approaches positive infinity and when x approached
negative infinity. One of my answer ( which is think it is correct one)  is
-7/8. This answer is derived from the rule in asymptotes that when x
approaches infinity, the limit is the coefficient of x when the the degree
of the numerator and denominator are both equal. Therefore, this is how i
find (-7/8) when x approaches plus infinity. However, when I type in this
answer in the box, the webwork doesn’t approve that this is a correct
answer because there is no green mark appears.

For the horizontal limit when x approaches negative infinity, I’m pretty
clueless. I know that If i can find the other horizontal asymptote( which i
guess that y must be positive), i can find the 2nd horizontal limit.Right
now, i can guess that number for both limits are not the same, since the
degree of the equation is x^3.
Can you give me more explanation on how to solve this problem ?

Khanh Linh Nguyen

Fall’12-Math 2207-HMWA