Limits at infinity - exponential functions

Evaluate exponential limits at infinity with a slide sequence of worked examples. Students connect end behavior and horizontal asymptotes with factoring a dominant exponential term.
Grades
High School
Pages
13
File type
Microsoft PowerPoint
Answer key
Included

Updated Sep 18, 2021

Subject
Math, Algebra, Calculus
Topic
Limits at infinity, Exponential functions
Resource types
Lesson Plans, Presentations
Answer key
Included

Product description

From the author

PowerPoint presentation, 13 slides explaining how to calculate the limit of exponential functions, as the function approaches either to positive or negative infinity.

In the classroom

Teaching tips & learning objectives

Learning objectives

  • Understand the concept of limits at infinity and horizontal asymptotes for exponential functions

Teaching tips

  • This deck explicitly builds on a prior lesson on limits at infinity of polynomials (slide 2); review that factoring-the-dominant-term technique before this lesson so students recognize it being reapplied to exponential expressions.

  • Walk through the sign of the exponent's own limit first (slides 5-6) before moving to the multi-term factoring examples (slides 9-12), since later problems depend on correctly reading whether the exponent itself goes to positive or negative infinity.

Skills covered

  • Evaluating basic exponential limits at infinity — recognizing that e^x -> infinity as x -> infinity and e^x -> 0 as x -> -infinity

  • Applying the limit-of-a-product property when the exponent of an exponential term is itself a polynomial limit

  • Factoring out the dominant exponential term in a multi-term expression to evaluate a limit at infinity

Good to know

Questions teachers ask about this resource

How does this lesson connect to limits of polynomials?

It explicitly reuses the polynomial-limits technique of factoring out the dominant term, applying the same idea to exponential expressions by factoring out an appropriate dominant exponential term for the direction of the limit, using the denominator’s growth when working with fractions.

What kinds of limit problems are worked through?

The slides progress from simple direct-evaluation limits of e^x, to limits where the exponent is itself a polynomial limit, to more involved rational expressions with exponential terms in both the numerator and denominator.

No reviews yet

Downloaded this resource? Tell other teachers how it went.

Resource details

Concepts & topics

Core concepts

  • Limits at infinity

  • Exponential functions

  • Horizontal asymptotes

Explore more

Categories this resource belongs to

Explore related searches

More to explore

You may also like