Table of contents
- 0. Fundamental Concepts of Algebra3h 29m
- 1. Equations and Inequalities3h 27m
- 2. Graphs1h 43m
- 3. Functions & Graphs2h 17m
- 4. Polynomial Functions1h 54m
- 5. Rational Functions1h 23m
- 6. Exponential and Logarithmic Functions2h 28m
- 7. Measuring Angles40m
- 8. Trigonometric Functions on Right Triangles2h 5m
- 9. Unit Circle1h 19m
- 10. Graphing Trigonometric Functions1h 19m
- 11. Inverse Trigonometric Functions and Basic Trig Equations1h 41m
- 12. Trigonometric Identities 2h 34m
- 13. Non-Right Triangles1h 38m
- 14. Vectors2h 25m
- 15. Polar Equations2h 5m
- 16. Parametric Equations1h 6m
- 17. Graphing Complex Numbers1h 7m
- 18. Systems of Equations and Matrices3h 6m
- 19. Conic Sections2h 36m
- 20. Sequences, Series & Induction1h 15m
- 21. Combinatorics and Probability1h 45m
- 22. Limits & Continuity1h 49m
- 23. Intro to Derivatives & Area Under the Curve2h 9m
22. Limits & Continuity
Finding Limits Algebraically
Struggling with Precalculus?
Join thousands of students who trust us to help them ace their exams!Watch the first videoMultiple Choice
Find the limit.
limx→2x−3x2−7x+12
A
−1
B
−2
C
0
D
DNE

1
First, identify the type of limit problem. This is a rational function where both the numerator and the denominator are polynomials.
Check if direct substitution of x = 2 into the function results in an indeterminate form like 0/0. Substitute x = 2 into the numerator and denominator: \( x^2 - 7x + 12 \) and \( x - 3 \).
Calculate the numerator: \( 2^2 - 7(2) + 12 = 4 - 14 + 12 = 2 \). Calculate the denominator: \( 2 - 3 = -1 \). Since the denominator is not zero, direct substitution is possible.
Since direct substitution does not result in an indeterminate form, evaluate the limit by substituting x = 2 directly into the function: \( \frac{2^2 - 7(2) + 12}{2 - 3} \).
Simplify the expression to find the limit. The limit is the value of the function as x approaches 2.
Watch next
Master Finding Limits by Direct Substitution with a bite sized video explanation from Patrick
Start learningRelated Videos
Related Practice