Short-cuts for limits of quotients of polynomials functions where x →∞

Use for these types:

lim     Axⁿ + terms containing lower powers of x
x→∞  Bx^m + terms containing lower powers of x

3 possible results:

1) If n=m:     Answer: A/B   (highest powers in top & bottom are equal)

2) If n>m:     Answer: no limit   (highest power in top greater than that of bottom)

3) If n<m:     Amswer: 0   (highest power in bottom is greater than that of the top)

Note:  Short-cuts are also valid if x→ -∞