Finding Limits Algebraically - Expii
In the simplest cases we can evaluate limits by substitution. Other limits, such as when we compute derivatives at a point later on, might require a little algebraic manipulation first (usually factoring and "canceling" common factors). Limit rules (such as limits of sums, differences, and constant multiples) and the squeeze theorem can sometimes help too. Limits of common functions (such as rational functions) are particularly important.