Skip to main content
Ch. 2 - Limits
Briggs - Calculus: Early Transcendentals 3rd Edition
Briggs3rd EditionCalculus: Early TranscendentalsISBN: 9780136847243Not the one you use?Change textbook
All textbooksBriggs 3rd EditionCh. 2 - LimitsProblem 2.28
Chapter 2, Problem 2.28

Determine the following limits. 


lim x→∞ x^4+7 / x^5+x^2−x

Verified step by step guidance
1
Identify the highest power of x in the numerator and the denominator. In this case, the highest power in the numerator is x^4 and in the denominator is x^5.
Divide every term in the numerator and the denominator by x^5, the highest power of x in the denominator.
Rewrite the expression: \( \lim_{{x \to \infty}} \frac{x^4/x^5 + 7/x^5}{x^5/x^5 + x^2/x^5 - x/x^5} \).
Simplify each term: \( \lim_{{x \to \infty}} \frac{1/x + 7/x^5}{1 + 1/x^3 - 1/x^4} \).
Evaluate the limit as x approaches infinity. As x becomes very large, terms with x in the denominator approach zero.

Verified video answer for a similar problem:

This video solution was recommended by our tutors as helpful for the problem above.
Video duration:
4m
Was this helpful?

Key Concepts

Here are the essential concepts you must grasp in order to answer the question correctly.

Limits at Infinity

Limits at infinity involve evaluating the behavior of a function as the variable approaches infinity. In this context, we analyze how the function behaves when x becomes very large, which often simplifies the expression by focusing on the highest degree terms in the numerator and denominator.
Recommended video:
05:50
One-Sided Limits

Polynomial Functions

Polynomial functions are expressions that consist of variables raised to non-negative integer powers, combined using addition, subtraction, and multiplication. Understanding the degrees of the polynomials in both the numerator and denominator is crucial for determining the limit, as the highest degree terms dominate the behavior of the function as x approaches infinity.
Recommended video:
6:04
Introduction to Polynomial Functions

Dominant Terms

Dominant terms are the terms in a polynomial that have the highest degree and thus have the most significant impact on the function's value as x approaches infinity. In the limit calculation, we can simplify the expression by focusing only on these dominant terms, allowing us to easily determine the limit's value.
Recommended video:
2:02
Simplifying Trig Expressions Example 1
Related Practice
Textbook Question

Sketch a graph of f and use it to make a conjecture about the values of f(a), lim x→a^−f(x),lim x→a^+f(x), and lim x→a f(x) or state that they do not exist.

f(x) = x^2+x−2 / x−1; a=1

1
views
Textbook Question

Evaluate f(3) if lim x→3^− f(x)=5,lim x→3^+ f(x)=6, and f is right-continuous at x=3.

Textbook Question

Determine the following limits. 

lim θ→∞ cos θ / θ2

1
views
Textbook Question

Determine the following limits.

lim x→3 1/ x − 3(1 /√x + 1 − 1/2)

Textbook Question

Determine the following limits.


limθ→02+sinθ1−cos2θ{\(\displaystyle\[\lim\)_{\(\theta\]\to\)0}}\(\frac{2+\sin\theta}{1-\cos^2\theta}\)

1
views
Textbook Question

Determine the end behavior of the following transcendental functions by analyzing appropriate limits. Then provide a simple sketch of the associated graph, showing asymptotes if they exist. 

f(x)=−3e−xf\(\left\)(x\(\right\))=-3e^{-x}

1
views