1. Limit as x-Approaches +/- Infinity
Looking for the highest power of a variable:
Example: x4 – 3x2 + 5x, then x4 is the highest power.
Three possibilities:
Highest power of variable in numerator
Highest power of variable in denominator
Equal highest power only

2. Limit as x-Approaches +/- Infinity
Highest power of variable in numerator
Limit is either positive or negative infinity.
Divide highest power of numerator by highest power of denominator.
Take resulting rational quotient and plug in x value.
Check signs and exponent to determine +/-

3. Limit as x-Approaches +/- Infinity
Highest power of variable in denominator
Limit is zero.

4. Limit as x-Approaches +/- Infinity
Equal highest power only
Limit is the resulting fraction of the coefficients.