Math Problem Statement

Evaluate the limit: lim (x → ∞) (2x²) / (x² + 1)

Solution

The problem asks to evaluate the limit:

limx2x2x2+1\lim_{x \to \infty} \frac{2x^2}{x^2 + 1}

Step-by-Step Solution:

  1. Identify the highest degree terms: The degrees of both the numerator and denominator are the same (both are x2x^2). This is crucial for determining how the limit behaves as xx approaches infinity.

  2. Factor out the highest power of xx from both the numerator and the denominator: 2x2x2+1=x2(2)x2(1+1x2)\frac{2x^2}{x^2 + 1} = \frac{x^2(2)}{x^2(1 + \frac{1}{x^2})}

  3. Simplify the expression: x2(2)x2(1+1x2)=21+1x2\frac{x^2(2)}{x^2(1 + \frac{1}{x^2})} = \frac{2}{1 + \frac{1}{x^2}}

  4. Take the limit as xx \to \infty: As xx goes to infinity, 1x20\frac{1}{x^2} \to 0. Therefore, the expression simplifies to: 21+0=2\frac{2}{1 + 0} = 2

Final Answer:

limx2x2x2+1=2\lim_{x \to \infty} \frac{2x^2}{x^2 + 1} = 2

Would you like a more detailed explanation or have any further questions?


Here are 5 related questions to expand on this:

  1. How would you evaluate limx3x3x3+2x\lim_{x \to \infty} \frac{3x^3}{x^3 + 2x}?
  2. What happens if the degree of the numerator is higher than the denominator?
  3. How would the limit change if the degrees of the numerator and denominator were different?
  4. Can you apply L'Hopital's Rule to this limit problem? Why or why not?
  5. What happens if you substitute x=0x = 0 in the given function?

Tip: When dealing with rational functions and limits at infinity, always check the degrees of the highest power terms in both the numerator and denominator. This helps determine the limit behavior efficiently!

Ask a new question for Free

By Image

Drop file here or Click Here to upload

Math Problem Analysis

Mathematical Concepts

Calculus
Limits at Infinity
Rational Functions

Formulas

lim (x → ∞) (ax^n) / (bx^n + c) = a/b when n is the highest power in both numerator and denominator

Theorems

Limit Laws
Degree Comparison of Polynomial Functions

Suitable Grade Level

Grades 11-12, College Level