Advanced Infinite Limits with Trigonometric, Exponential, and Logarithmic Functions

Reviewed by Editorial Team
The ProProfs editorial team is comprised of experienced subject matter experts. They've collectively created over 10,000 quizzes and lessons, serving over 100 million users. Our team includes in-house content moderators and subject matter experts, as well as a global network of rigorously trained contributors. All adhere to our comprehensive editorial guidelines, ensuring the delivery of high-quality content.
Learn about Our Editorial Process
| By Thames
T
Thames
Community Contributor
Quizzes Created: 7682 | Total Attempts: 9,547,133
| Questions: 15 | Updated: Dec 17, 2025
Please wait...
Question 1 / 15
0 %
0/100
Score 0/100
1) Evaluate the limit: lim(x→-2) 3/(x+2)²

Explanation

When x approaches -2, the denominator (x+2)² becomes very small. Since we're squaring the difference, the denominator is always positive regardless of whether x approaches -2 from the left or right. As the denominator approaches zero while remaining positive, the fraction 3/(x+2)² grows without bound. The constant numerator 3 doesn't change this behavior. Therefore, the limit is infinity.

Submit
Please wait...
About This Quiz
Advanced Infinite Limits With Trigonometric, Exponential, And Logarithmic Functions - Quiz

Ready to handle infinite limits in full calculus style? This quiz challenges you with limits involving higher-degree polynomials, exponential growth, logarithms, and classic ∞/∞ and 0/0 forms. You’ll use L’Hôpital’s Rule and leading-term analysis to compare growth rates of polynomials vs. exponentials and logs, determine horizontal and vertical asymptotes, and... see moreanalyze one-sided limits that go to +∞ or −∞. Along the way, you’ll interpret statements like lim f(x) = ∞ in terms of the graph and decide where vertical asymptotes occur or where there are just holes. This quiz ties together infinite limits, asymptotes, and advanced function behavior in preparation for deeper calculus work.
see less

2)
You may optionally provide this to label your report, leaderboard, or certificate.
2) Consider the function f(x) = 2/(x-4). What happens to f(x) as x approaches 4 from the left?

Explanation

When x approaches 4 from the left, x is slightly less than 4. This means x-4 is a small negative number. As x gets closer to 4 from the left, x-4 becomes smaller and smaller negative values. Dividing 2 by increasingly small negative numbers produces increasingly large negative values. Therefore, as x approaches 4 from the left, f(x) approaches negative infinity.

Submit
3) Evaluate the limit: lim(x→∞) (4x³ + 2x² - 5)/(2x³ - x + 3)

Explanation

To evaluate this limit at infinity, we divide both numerator and denominator by the highest power of x in the denominator, which is x³. This gives us: lim(x→∞) (4 + 2/x - 5/x³)/(2 - 1/x² + 3/x³). As x approaches infinity, terms with x in the denominator (2/x, 5/x³, 1/x², and 3/x³) all approach 0. This simplifies our expression to (4 + 0 - 0)/(2 - 0 + 0) = 4/2 = 2. Therefore, the limit equals 2.

Submit
4) The True or False: If lim_{x→a} f(x) = ∞, then the graph of f(x) has a vertical asymptote at x = a.

Explanation

This is the definition of a vertical asymptote. If the function values grow without bound (approaching positive or negative infinity) as x gets arbitrarily close to a specific number a, then the vertical line x = a is a vertical asymptote for the graph of the function.

Submit
5) Evaluate the limit: lim(x→(π/2)⁺) tan(x)

Explanation

The tangent function is defined as tan(x) = sin(x)/cos(x). As x approaches π/2 from the right, sin(x) approaches 1 and cos(x) approaches 0 from the negative side (since cosine is negative in the second quadrant). When we divide a value approaching 1 by values approaching 0 from the negative side, the result grows without bound in the negative direction. Therefore, lim(x→(π/2)⁺) tan(x) = -∞.

Submit
6) For the piecewise function f(x) = {1/(x+3) if x < -3, -2 if x ≥ -3}, what is lim(x→-3⁻) f(x)?

Explanation

Since we're approaching x = -3 from the left (x

Submit
7) Evaluate the limit: limx→0⁻ 1/x3

Explanation

As x approaches 0 from the left, x is negative and getting closer to zero. When we cube a negative number, the result remains negative. So x³ is a small negative number. When we divide 1 by increasingly small negative numbers, the result grows without bound in the negative direction. Therefore, lim(x→0⁻) 1/x³ = -∞.

Submit
8) Evaluate the limit: lim(x→∞) (x^4 + 3x² - 2)/(2x³ + 5x - 1)

Explanation

To evaluate this limit at infinity, we compare the degrees of the polynomials in the numerator and denominator. The numerator has degree 4 (highest power is x^4) and the denominator has degree 3 (highest power is x³). When the degree of the numerator is greater than the degree of the denominator, the limit at infinity will be infinite. Since the leading coefficient of the numerator (1) is positive, and for large positive x values, the function will be positive, the limit approaches positive infinity.

Submit
9) Evaluate the limit: lim(x→1+) (x³ - 1)/(x² - 2x + 1)

Explanation

First, we factor both numerator and denominator. The numerator x³ - 1 = (x - 1)(x² + x + 1) using the difference of cubes formula. The denominator x² - 2x + 1 = (x - 1)². This gives us: lim(x→1) (x - 1)(x² + x + 1)/(x - 1)² = lim(x→1) (x² + x + 1)/(x - 1). As x approaches 1, the numerator approaches 1² + 1 + 1 = 3, while the denominator approaches 0. Since the denominator approaches 0 while the numerator approaches a non-zero value, the limit is infinite. Specifically, as x approaches 1 from the right, the denominator is positive, so the limit is +∞.

Submit
10) Determine the behavior of f(x) = (2x² - 3x + 1)/(x² - 9) as x approaches 3 from the left.

Explanation

As x approaches 3 from the left, the denominator x² - 9 approaches 0 from the negative side because x² will be slightly less than 9. The numerator 2x² - 3x + 1 approaches 2(9) - 3(3) + 1 = 18 - 9 + 1 = 10, which is positive. When we divide a positive number (approximately 10) by increasingly small negative numbers, the result grows without bound in the negative direction. Therefore, as x approaches 3 from the left, f(x) approaches negative infinity.

Submit
11) Evaluate the limit: lim(x→-∞) (4x⁵ + 2x³ - x)/(2x⁵ - 3x² + 1)

Explanation

To evaluate this limit at negative infinity, we divide both numerator and denominator by the highest power of x, which is x⁵. This gives us: lim(x→-∞) (4 + 2/x² - 1/x^4)/(2 - 3/x³ + 1/x⁵). As x approaches negative infinity, all terms with x in the denominator (2/x², 1/x^4, 3/x³, and 1/x⁵) approach 0. This simplifies our expression to (4 + 0 - 0)/(2 - 0 + 0) = 4/2 = 2. Therefore, the limit equals 2.

Submit
12) For the function f(x) = ln(x)/(x-1), determine the behavior as x approaches 1 from the right.

Explanation

As x approaches 1 from the right, both the numerator ln(x) and the denominator (x-1) approach 0, giving us the indeterminate form 0/0. We can apply L'Hôpital's Rule by taking derivatives of numerator and denominator: the derivative of ln(x) is 1/x, and the derivative of (x-1) is 1. This gives us lim(x→1⁺) (1/x)/1 = lim(x→1⁺) 1/x = 1/1 = 1. Therefore, as x approaches 1 from the right, f(x) approaches 1.

Submit
13) Evaluate the limit: lim(x→0) (1 - cos(x))/x²

Explanation

As x approaches 0, both the numerator (1 - cos(x)) and the denominator x² approach 0, giving us the indeterminate form 0/0. We can apply L'Hôpital's Rule by taking derivatives of numerator and denominator: the derivative of (1 - cos(x)) is sin(x), and the derivative of x² is 2x. This gives us lim(x→0) sin(x)/(2x). This is still 0/0, so we apply L'Hôpital's Rule again: the derivative of sin(x) is cos(x), and the derivative of 2x is 2. This gives us lim(x→0) cos(x)/2 = cos(0)/2 = 1/2. Therefore, the limit equals 1/2.

Submit
14) Evaluate the limit: lim(x→∞) (ln(x))/√x

Explanation

This limit is in the indeterminate form ∞/∞, so we can apply L'Hôpital's Rule. Taking derivatives of numerator and denominator gives us lim(x→∞) (1/x)/(1/(2√x)) = lim(x→∞) (1/x)·(2√x/1) = lim(x→∞) 2/√x. As x approaches infinity, √x also approaches infinity, so 2/√x approaches 0. Therefore, the original limit equals 0.

Submit
15) Determine the vertical asymptotes of f(x) = (x² - 4)/(x³ - 8)

Explanation

First, we factor both numerator and denominator. The numerator x² - 4 = (x - 2)(x + 2). The denominator x³ - 8 = (x - 2)(x² + 2x + 4) using the difference of cubes formula. This gives us f(x) = (x - 2)(x + 2)/[(x - 2)(x² + 2x + 4)]. For x ≠ 2, we can cancel the (x - 2) factors, resulting in f(x) = (x + 2)/(x² + 2x + 4). At x = 2, both numerator and denominator of the original function are zero, but after simplification, the function approaches (2 + 2)/(4 + 4 + 4) = 4/12 = 1/3. This implies the graph has a hole at x = 2, not a vertical asymptote. The quadratic x² + 2x + 4 in the denominator has discriminant b² - 4ac = 4 - 16 = -12, which is negative, so it has no real roots. Therefore, the function has no vertical asymptotes.

Submit
×
Saved
Thank you for your feedback!
View My Results
Cancel
  • All
    All (15)
  • Unanswered
    Unanswered ()
  • Answered
    Answered ()
Evaluate the limit: lim(x→-2) 3/(x+2)²
Consider the function f(x) = 2/(x-4). What happens to f(x) as x...
Evaluate the limit: lim(x→∞) (4x³ + 2x² - 5)/(2x³ - x + 3)
The True or False: If lim_{x→a} f(x) = ∞, then the graph of f(x)...
Evaluate the limit: lim(x→(π/2)⁺) tan(x)
For the piecewise function f(x) = {1/(x+3) if x < -3, -2 if x ≥...
Evaluate the limit: limx→0⁻ 1/x3
Evaluate the limit: lim(x→∞) (x^4 + 3x² - 2)/(2x³ + 5x - 1)
Evaluate the limit: lim(x→1+) (x³ - 1)/(x² - 2x + 1)
Determine the behavior of f(x) = (2x² - 3x + 1)/(x² - 9) as x...
Evaluate the limit: lim(x→-∞) (4x⁵ + 2x³ - x)/(2x⁵ - 3x² +...
For the function f(x) = ln(x)/(x-1), determine the behavior as x...
Evaluate the limit: lim(x→0) (1 - cos(x))/x²
Evaluate the limit: lim(x→∞) (ln(x))/√x
Determine the vertical asymptotes of f(x) = (x² - 4)/(x³ - 8)
Alert!

Advertisement