Table of contents
- 0. Functions7h 52m
- Introduction to Functions16m
- Piecewise Functions10m
- Properties of Functions9m
- Common Functions1h 8m
- Transformations5m
- Combining Functions27m
- Exponent rules32m
- Exponential Functions28m
- Logarithmic Functions24m
- Properties of Logarithms34m
- Exponential & Logarithmic Equations35m
- Introduction to Trigonometric Functions38m
- Graphs of Trigonometric Functions44m
- Trigonometric Identities47m
- Inverse Trigonometric Functions48m
- 1. Limits and Continuity2h 2m
- 2. Intro to Derivatives1h 33m
- 3. Techniques of Differentiation3h 18m
- 4. Applications of Derivatives2h 38m
- 5. Graphical Applications of Derivatives6h 2m
- 6. Derivatives of Inverse, Exponential, & Logarithmic Functions2h 37m
- 7. Antiderivatives & Indefinite Integrals1h 26m
1. Limits and Continuity
Introduction to Limits
Problem 7b
Textbook Question
Let f(x)=x−2x2−4. <IMAGE>
Make a conjecture about the value of x→2limx−2x2−4.

1
First, recognize that the expression \( \frac{x^2 - 4}{x - 2} \) is undefined at \( x = 2 \) because it results in division by zero. Therefore, we need to simplify the expression to evaluate the limit.
Notice that the numerator \( x^2 - 4 \) can be factored as a difference of squares: \( x^2 - 4 = (x - 2)(x + 2) \).
Substitute the factored form into the original expression: \( \frac{(x - 2)(x + 2)}{x - 2} \).
Cancel the common factor \( (x - 2) \) in the numerator and the denominator, which simplifies the expression to \( x + 2 \), provided \( x \neq 2 \).
Now, evaluate the limit of the simplified expression as \( x \to 2 \): \( \lim_{x \to 2} (x + 2) \). This can be directly computed by substituting \( x = 2 \) into the expression, leading to the conjecture about the limit.
Recommended similar problem, with video answer:

This video solution was recommended by our tutors as helpful for the problem above
Video duration:
2mPlay a video:
Was this helpful?
Watch next
Master Finding Limits Numerically and Graphically with a bite sized video explanation from Callie
Start learning