zuai-logo
zuai-logo
  1. AP Calculus
FlashcardFlashcard
Study GuideStudy GuideQuestion BankQuestion BankGlossaryGlossary

What are the differences between limits at infinity and limits at a finite number?

Limits at infinity: x approaches ∞ or -∞, examining end behavior. Limits at a finite number: x approaches a specific value, examining local behavior.

Flip to see [answer/question]
Flip to see [answer/question]
Revise later
SpaceTo flip
If confident

All Flashcards

What are the differences between limits at infinity and limits at a finite number?

Limits at infinity: x approaches ∞ or -∞, examining end behavior. Limits at a finite number: x approaches a specific value, examining local behavior.

What are the differences between horizontal and vertical asymptotes?

Horizontal: y-value function approaches as x approaches infinity. Vertical: x-value function approaches infinity.

Compare the growth rates of polynomial and exponential functions.

Polynomial: Grows at a polynomial rate (e.g., x2x^2x2, x3x^3x3). Exponential: Grows at an exponential rate (e.g., 2x2^x2x, exe^xex). Exponential growth is much faster.

Compare the behavior of 1x\frac{1}{x}x1​ and 1x2\frac{1}{x^2}x21​ as x approaches infinity.

Both approach 0. 1x\frac{1}{x}x1​ can be positive or negative depending on the sign of x, while 1x2\frac{1}{x^2}x21​ is always positive.

Contrast the limits of sin⁡(x)\sin(x)sin(x) and sin⁡(x)x\frac{\sin(x)}{x}xsin(x)​ as x approaches infinity.

sin⁡(x)\sin(x)sin(x): Limit DNE (oscillates). sin⁡(x)x\frac{\sin(x)}{x}xsin(x)​: Limit is 0 (Squeeze Theorem).

Compare the end behavior of x2x^2x2 and x3x^3x3.

x2x^2x2: As x approaches ±∞, x2x^2x2 approaches +∞. x3x^3x3: As x approaches +∞, x3x^3x3 approaches +∞. As x approaches -∞, x3x^3x3 approaches -∞.

Compare horizontal asymptotes with removable discontinuities.

Horizontal Asymptotes: Describe the end behavior of a function. Removable Discontinuities: Points where the function is not defined but could be redefined to be continuous.

Compare the limits of ln⁡(x)\ln(x)ln(x) and exe^xex as x approaches infinity.

ln⁡(x)\ln(x)ln(x): Approaches infinity, but very slowly. exe^xex: Approaches infinity very quickly.

What is the difference between an infinite limit and a limit at infinity?

Infinite Limit: The function approaches infinity as x approaches a finite value. Limit at Infinity: The function approaches a finite value or infinity as x approaches infinity.

Compare the limits of x+1x\frac{x+1}{x}xx+1​ and xx+1\frac{x}{x+1}x+1x​ as x approaches infinity.

x+1x\frac{x+1}{x}xx+1​: Approaches 1. xx+1\frac{x}{x+1}x+1x​: Approaches 1.

Define 'limit'.

The value that a function approaches as the input approaches some value.

What is a horizontal asymptote?

A y-value that the graph of a function approaches as x tends to +∞ or -∞.

Define 'end behavior'.

The behavior of a function as x approaches positive or negative infinity.

What is an oscillating function?

A function that repeatedly fluctuates between two or more values as x approaches infinity.

Define the Squeeze Theorem.

If g(x) ≤ f(x) ≤ h(x) for all x near c, and lim x→c g(x) = L = lim x→c h(x), then lim x→c f(x) = L.

What is meant by 'growth rate' in the context of functions?

The speed at which a function's output increases as its input increases.

Define a rational function.

A function that can be defined as a fraction where both the numerator and denominator are polynomials.

What is the degree of a polynomial?

The highest power of the variable in the polynomial.

Define 'leading coefficient'.

The coefficient of the term with the highest power in a polynomial.

What does DNE stand for in the context of limits?

Does Not Exist

How do you find the horizontal asymptote of f(x)=3x2+1x2−2f(x) = \frac{3x^2 + 1}{x^2 - 2}f(x)=x2−23x2+1​?

Compare degrees of numerator and denominator. They are equal (degree 2). Divide leading coefficients: 3/1 = 3. HA is y = 3.

How do you evaluate lim⁡x→∞xex\lim_{x \to \infty} \frac{x}{e^x}limx→∞​exx​?

Recognize exponential growth is faster than polynomial. The limit is 0.

How do you find horizontal asymptotes of rational functions?

Compare the degrees of the numerator and denominator. Apply the 'bottom heavy', 'top heavy', or 'equal degree' rules.

How do you evaluate limits involving oscillating functions at infinity?

Check if the oscillating function is divided by a function that approaches infinity. If so, the Squeeze Theorem often applies, resulting in a limit of 0. Otherwise, the limit DNE.

How do you evaluate lim⁡x→∞4x+sin⁡(x)x\lim_{x \to \infty} \frac{4x + \sin(x)}{x}limx→∞​x4x+sin(x)​?

Divide each term by x: lim⁡x→∞(4+sin⁡(x)x)\lim_{x \to \infty} (4 + \frac{\sin(x)}{x})limx→∞​(4+xsin(x)​). Since lim⁡x→∞sin⁡(x)x=0\lim_{x \to \infty} \frac{\sin(x)}{x} = 0limx→∞​xsin(x)​=0, the limit is 4.

How do you determine the end behavior of a polynomial function?

Consider the leading term of the polynomial. If the degree is even, both ends go to +∞ or -∞ (depending on the sign of the leading coefficient). If the degree is odd, one end goes to +∞ and the other to -∞.

How do you evaluate lim⁡x→∞ln⁡(x)x\lim_{x \to \infty} \frac{\ln(x)}{x}limx→∞​xln(x)​?

Recognize that polynomial growth is faster than logarithmic. The limit is 0.

How to find vertical asymptotes of a rational function?

Set the denominator equal to zero and solve for x. These x-values are potential vertical asymptotes.

How do you evaluate lim⁡x→−∞ex\lim_{x \to -\infty} e^xlimx→−∞​ex?

As x approaches negative infinity, exe^xex approaches 0.

How do you solve for horizontal asymptotes when given a function?

Solve for lim⁡x→∞f(x)\lim_{x \to \infty} f(x)limx→∞​f(x) and lim⁡x→−∞f(x)\lim_{x \to -\infty} f(x)limx→−∞​f(x).