Summary of the Limit Laws

Essential Concepts

  • The limit laws allow us to evaluate limits of functions without having to go through step-by-step processes each time.
  • For polynomials and rational functions, limxaf(x)=f(a).
  • You can evaluate the limit of a function by factoring and canceling, by multiplying by a conjugate, or by simplifying a complex fraction.
  • The Squeeze Theorem allows you to find the limit of a function if the function is always greater than one function and less than another function with limits that are known.

Key Equations

  • Basic Limit Results
    limxax=a
    limxac=c
  • Important Limits
    limθ0sinθ=0
    limθ0cosθ=1
    limθ0sinθθ=1
    limθ01cosθθ=0

Glossary

infinite limit
A function has an infinite limit at a point a if it either increases or decreases without bound as it approaches a
intuitive definition of the limit
If all values of the function f(x) approach the real number L as the values of x(a) approach a, f(x) approaches L
one-sided limit
A one-sided limit of a function is a limit taken from either the left or the right
vertical asymptote
A function has a vertical asymptote at x=a if the limit as x approaches a from the right or left is infinite