Unit 1: Limits and Continuity Flashcards
What is the definition of a limit?
A limit is the value that a function approaches as the input approaches a certain point.
True or False: The limit of a function can be different from the function’s value at that point.
True
Fill in the blank: The notation for the limit of f(x) as x approaches a is ______.
lim(x→a) f(x)
What is the Squeeze Theorem used for?
It is used to find limits of functions that are squeezed between two other functions.
What does it mean for a limit to be infinite?
It means that the function increases or decreases without bound as it approaches a certain point.
What is the formal definition of continuity at a point?
A function is continuous at a point if the limit as x approaches the point equals the function’s value at that point.
Multiple choice: Which of the following is a requirement for a function to be continuous at x = c? A) f(c) exists B) lim(x→c) f(x) exists C) lim(x→c) f(x) = f(c) D) All of the above
D) All of the above
What is an asymptote?
An asymptote is a line that a graph approaches but never touches.
True or False: Vertical asymptotes occur where a function approaches infinity.
True
What is the difference between a removable and a non-removable discontinuity?
A removable discontinuity can be ‘fixed’ by redefining the function at that point, while a non-removable discontinuity cannot be fixed.
What is the Intermediate Value Theorem?
The IVT states that if f is continuous on the interval [a,b] and N is a value between f(a) and f(b), then there exists at least one c in (a,b) such that f(c)=N.
Multiple choice: If a function has a limit of 0 as x approaches 2, what can we conclude? A) f(2) = 0 B) f(x) approaches 0 as x approaches 2 C) f(2) does not exist D) All of the above
B) f(x) approaches 0 as x approaches 2
What does it mean for a limit to exist?
A limit exists if the left-hand limit and the right-hand limit as 𝑥 approaches a point 𝑐 are equal.
Define a one-sided limit.
A one-sided limit is the value a function approaches as the input approaches a specific point from either the left or right.
What are the three types of discontinuities?
- Removable Discontinuity (hole in the graph)
- Jump Discontinuity (sudden jump in values)
- Infinite Discontinuity (vertical asymptote)
Squeeze Theorem
f(x)≤g(x)≤h(x) for all numbers, and at some point x=k we have f(k)=h(k), then g(k) must also be equal to them
How do you evaluate limits at infinity?
To evaluate limits at infinity, analyze the end behavior of the function as x→∞ or x→−∞ by comparing the degrees of the terms in the numerator and denominator (for rational functions).
What is the difference between horizontal and vertical asymptotes?
Horizontal asymptotes occur as x→±∞ and indicate the end behavior of a function.
Vertical asymptotes occur at values of 𝑥 where the function approaches infinity or negative infinity, typically where the denominator is zero in a rational function.
State the Constant Multiple Law for limits.
If lim x→c f(x)=L and 𝑘 is a constant, then lim x→c k⋅f(x)=k⋅L
What is the Sum Law for limits?
If lim x→c f(x) = L and lim x→c g(x) = M, then lim (f(x) + g(x)) = L + M
What is the Difference Law for limits?
If lim x→c f(x) = L and lim x→c g(x) = M, then lim x→c (f(x) − g(x)) = L − M
What is the Constant Multiple Law for limits?
If lim x→c f(x) = L and k is a constant, then lim x→c (k ⋅ f(x)) = k ⋅ L