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→3x−3x−3
A
23
B
0
C
63
D
Does not exist

1
Identify the form of the limit: As x approaches 3, both the numerator and the denominator approach 0, indicating an indeterminate form 0/0. This suggests that we need to simplify the expression.
Rationalize the numerator: Multiply the numerator and the denominator by the conjugate of the numerator, which is (\(\sqrt{x} + \sqrt{3}\)). This will help eliminate the square roots in the numerator.
Simplify the expression: After multiplying, the numerator becomes \((x - 3)\) because \((\sqrt{x} - \sqrt{3})(\sqrt{x} + \sqrt{3}) = x - 3\). The denominator becomes \((x - 3)(\sqrt{x} + \sqrt{3})\).
Cancel the common factor: The \((x - 3)\) terms in the numerator and denominator cancel each other out, leaving \(\frac{1}{\sqrt{x} + \sqrt{3}}\).
Evaluate the limit: Substitute \(x = 3\) into the simplified expression \(\frac{1}{\sqrt{x} + \sqrt{3}}\) to find the limit as x approaches 3.
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