15. Find the following limit V2x+5–1 lim x→-2 x+2

Trigonometry (11th Edition)
11th Edition
ISBN:9780134217437
Author:Margaret L. Lial, John Hornsby, David I. Schneider, Callie Daniels
Publisher:Margaret L. Lial, John Hornsby, David I. Schneider, Callie Daniels
Chapter1: Trigonometric Functions
Section: Chapter Questions
Problem 1RE: 1. Give the measures of the complement and the supplement of an angle measuring 35°.
icon
Related questions
Question
### Calculus Problem: Evaluating a Limit

**Problem:**

15. Find the following limit

\[ \lim_{{x \to -2}} \frac{\sqrt{2x + 5} - 1}{x + 2} \]

### Steps to Solve the Limit:

1. **Direct Substitution:**
   Start by substituting \( x = -2 \) into the function to check if the limit can be directly evaluated:

   \[ \frac{\sqrt{2(-2) + 5} - 1}{-2 + 2} = \frac{\sqrt{-4 + 5} - 1}{0} = \frac{\sqrt{1} - 1}{0} = \frac{1 - 1}{0} = \frac{0}{0} \]

   Direct substitution results in an indeterminate form \(\frac{0}{0}\), which indicates that we need to use another method to evaluate the limit.

2. **Rationalizing the Numerator:**
   To resolve this, rationalize the numerator by multiplying the numerator and denominator by the conjugate of the numerator \(\sqrt{2x + 5} + 1\):

   \[ \frac{\sqrt{2x + 5} - 1}{x + 2} \cdot \frac{\sqrt{2x + 5} + 1}{\sqrt{2x + 5} + 1} \]

   The goal is to simplify the expression:

   \[ \frac{(\sqrt{2x + 5} - 1)(\sqrt{2x + 5} + 1)}{(x + 2)(\sqrt{2x + 5} + 1)} \]

   Using the difference of squares \( (a - b)(a + b) = a^2 - b^2 \):

   \[ = \frac{(2x + 5) - 1}{(x + 2)(\sqrt{2x + 5} + 1)} \]

   Simplify the numerator:

   \[ = \frac{2x + 4}{(x + 2)(\sqrt{2x + 5} + 1)} \]

   Factor the numerator:

   \[ = \frac{2(x + 2)}{(x + 2
Transcribed Image Text:### Calculus Problem: Evaluating a Limit **Problem:** 15. Find the following limit \[ \lim_{{x \to -2}} \frac{\sqrt{2x + 5} - 1}{x + 2} \] ### Steps to Solve the Limit: 1. **Direct Substitution:** Start by substituting \( x = -2 \) into the function to check if the limit can be directly evaluated: \[ \frac{\sqrt{2(-2) + 5} - 1}{-2 + 2} = \frac{\sqrt{-4 + 5} - 1}{0} = \frac{\sqrt{1} - 1}{0} = \frac{1 - 1}{0} = \frac{0}{0} \] Direct substitution results in an indeterminate form \(\frac{0}{0}\), which indicates that we need to use another method to evaluate the limit. 2. **Rationalizing the Numerator:** To resolve this, rationalize the numerator by multiplying the numerator and denominator by the conjugate of the numerator \(\sqrt{2x + 5} + 1\): \[ \frac{\sqrt{2x + 5} - 1}{x + 2} \cdot \frac{\sqrt{2x + 5} + 1}{\sqrt{2x + 5} + 1} \] The goal is to simplify the expression: \[ \frac{(\sqrt{2x + 5} - 1)(\sqrt{2x + 5} + 1)}{(x + 2)(\sqrt{2x + 5} + 1)} \] Using the difference of squares \( (a - b)(a + b) = a^2 - b^2 \): \[ = \frac{(2x + 5) - 1}{(x + 2)(\sqrt{2x + 5} + 1)} \] Simplify the numerator: \[ = \frac{2x + 4}{(x + 2)(\sqrt{2x + 5} + 1)} \] Factor the numerator: \[ = \frac{2(x + 2)}{(x + 2
Expert Solution
steps

Step by step

Solved in 2 steps with 2 images

Blurred answer
Knowledge Booster
Limits and Continuity
Learn more about
Need a deep-dive on the concept behind this application? Look no further. Learn more about this topic, trigonometry and related others by exploring similar questions and additional content below.
Recommended textbooks for you
Trigonometry (11th Edition)
Trigonometry (11th Edition)
Trigonometry
ISBN:
9780134217437
Author:
Margaret L. Lial, John Hornsby, David I. Schneider, Callie Daniels
Publisher:
PEARSON
Trigonometry (MindTap Course List)
Trigonometry (MindTap Course List)
Trigonometry
ISBN:
9781305652224
Author:
Charles P. McKeague, Mark D. Turner
Publisher:
Cengage Learning
Algebra and Trigonometry
Algebra and Trigonometry
Trigonometry
ISBN:
9781938168376
Author:
Jay Abramson
Publisher:
OpenStax
Trigonometry (MindTap Course List)
Trigonometry (MindTap Course List)
Trigonometry
ISBN:
9781337278461
Author:
Ron Larson
Publisher:
Cengage Learning