All Flashcards
Define a Limit.
The value that a function approaches as the input approaches a certain value.
What is an indeterminate form?
An expression whose limit cannot be evaluated directly (e.g., 0/0, ∞/∞).
Define L'Hôpital's Rule.
A method to evaluate limits of indeterminate forms by taking the derivative of the numerator and denominator.
What is the Squeeze Theorem?
If and , then .
Define Continuity.
A function is continuous at a point if the limit exists at that point, the function is defined at that point, and the limit equals the function value.
What is a rational function?
A function that can be expressed as the quotient of two polynomials.
Define a composite function.
A function that is formed by combining two functions, where the output of one function becomes the input of the other.
What is meant by algebraic manipulation?
The process of rewriting an expression using algebraic rules to simplify it or transform it into a more useful form.
What is a conjugate?
An expression formed by changing the sign between two terms in a binomial, often used to rationalize denominators.
What does it mean for a limit to 'not exist'?
The function does not approach a specific value as x approaches a certain point, or the left-hand limit and right-hand limit are not equal.
How does a hole in a graph relate to limits?
A hole indicates that the function is not defined at that x-value, but the limit may still exist if the function approaches a specific y-value.
How does a vertical asymptote on a graph relate to limits?
A vertical asymptote indicates that the limit approaches infinity (or negative infinity) as x approaches a certain value from one or both sides.
What does it mean if a graph oscillates rapidly near a point when considering limits?
It suggests that the limit does not exist because the function does not approach a single value.
How can you identify one-sided limits from a graph?
Examine the behavior of the function as x approaches the value from the left and from the right separately.
How does the graph of a function indicate continuity at a point?
The graph must not have any breaks, holes, or jumps at that point. You should be able to draw the graph through that point without lifting your pen.
How can a graph help visualize the Squeeze Theorem?
You can see the function being 'squeezed' between two other functions that converge to the same limit.
What does the graph of y = sin(x)/x tell us about its limit as x approaches 0?
The graph visually shows that as x approaches 0, the function approaches 1, even though the function is undefined at x = 0.
How does the slope of a tangent line on a graph relate to limits?
The slope of the tangent line at a point is the limit of the difference quotient as h approaches 0, which represents the derivative at that point.
How can you use a graph to determine infinite limits?
Look for vertical asymptotes. If the function approaches infinity (or negative infinity) as x approaches a certain value, then the limit is infinite.
How does a jump discontinuity affect the limit of a function?
The limit does not exist at a jump discontinuity because the left-hand limit and the right-hand limit are not equal.
How to find given a graph of ?
- Locate 'a' on the x-axis. 2. Follow the graph as x approaches 'a' from both sides. 3. Identify the y-value that the graph approaches. 4. That y-value is the limit.
How to find given a table of values?
- Look at x-values approaching 'a' from both sides. 2. Observe the corresponding y-values. 3. If y-values approach the same number, that's the limit.
How to evaluate if direct substitution yields 0/0?
- Try to factor and simplify the expression. 2. If simplification doesn't work, consider L'Hôpital's Rule. 3. Take the derivative of the numerator and denominator. 4. Evaluate the limit again.
How to evaluate if contains a radical?
- Multiply the numerator and denominator by the conjugate of the expression containing the radical. 2. Simplify the expression. 3. Evaluate the limit.
How to find where P and Q are polynomials?
- Divide both numerator and denominator by the highest power of x in the denominator. 2. Evaluate the limit as x approaches infinity. Terms like 1/x approach 0.
How to determine if a limit exists at a point?
- Find the limit from the left. 2. Find the limit from the right. 3. If the left-hand limit equals the right-hand limit, the limit exists and is equal to that value.
How to use the Squeeze Theorem to find a limit?
- Find two functions, f(x) and h(x), such that f(x) <= g(x) <= h(x). 2. Find the limits of f(x) and h(x) as x approaches a. 3. If both limits are equal to L, then the limit of g(x) as x approaches a is also L.
How to find the limit of a composite function ?
- Find . 2. Find . 3. If this limit exists, it is the limit of the composite function.
How to deal with piecewise functions when finding limits?
- Determine which piece of the function applies as x approaches the target value. 2. Evaluate the limit using that piece of the function. 3. If the target value is the boundary, check both left and right limits.
How to choose between algebraic manipulation and direct substitution?
- First, try direct substitution. 2. If direct substitution results in an indeterminate form, then use algebraic manipulation techniques.