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How to find vertical asymptotes of a rational function?

  1. Factor numerator and denominator. 2. Simplify the function. 3. Find values where the denominator is zero and the numerator is non-zero.
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How to find vertical asymptotes of a rational function?

  1. Factor numerator and denominator. 2. Simplify the function. 3. Find values where the denominator is zero and the numerator is non-zero.

How to show x=ax=a is a vertical asymptote using limits?

  1. Evaluate limxa+f(x)\lim_{x\to a^+} f(x). 2. Evaluate limxaf(x)\lim_{x\to a^-} f(x). 3. Show that at least one of these limits is ±\pm \infty.

How to determine if a discontinuity is removable or a vertical asymptote?

  1. Factor and simplify the function. 2. If a factor cancels, it's a removable discontinuity. 3. If a factor remains in the denominator, it's a vertical asymptote.

How to find the vertical asymptotes of f(x)=x+2x24f(x) = \frac{x+2}{x^2 - 4}?

  1. Factor: f(x)=x+2(x+2)(x2)f(x) = \frac{x+2}{(x+2)(x-2)}. 2. Simplify: f(x)=1x2f(x) = \frac{1}{x-2}. 3. VA at x=2x=2.

Steps to find vertical asymptotes of f(x)=tan(x)f(x) = \tan(x)?

  1. Rewrite as f(x)=sin(x)cos(x)f(x) = \frac{\sin(x)}{\cos(x)}. 2. Find where cos(x)=0\cos(x) = 0. 3. x=(2n+1)π2x = \frac{(2n+1)\pi}{2}, where n is an integer.

How to find the vertical asymptotes of f(x)=x21x1f(x) = \frac{x^2 - 1}{x-1}?

  1. Factor: f(x)=(x1)(x+1)x1f(x) = \frac{(x-1)(x+1)}{x-1}. 2. Simplify: f(x)=x+1f(x) = x+1. 3. Removable discontinuity at x=1, no vertical asymptote.

How to find the limit of a rational function as x approaches a vertical asymptote?

  1. Determine the sign of the function as x approaches from the left and right. 2. The limit will be either positive or negative infinity.

How to solve for vertical asymptotes of f(x)=1x2+1f(x) = \frac{1}{x^2 + 1}?

  1. Set denominator equal to zero: x2+1=0x^2 + 1 = 0. 2. Solve for x: x2=1x^2 = -1. 3. No real solutions, so no vertical asymptotes.

How to find vertical asymptotes of f(x)=exxf(x) = \frac{e^x}{x}?

  1. Check where the denominator is zero: x=0x=0. 2. Verify the numerator is not zero at x=0x=0: e0=10e^0 = 1 \neq 0. 3. Vertical asymptote at x=0x=0.

How to determine the behavior of f(x)=1x2f(x) = \frac{1}{x-2} as x approaches 2?

  1. Check limit from the right: limx2+1x2=\lim_{x\to 2^+} \frac{1}{x-2} = \infty. 2. Check limit from the left: limx21x2=\lim_{x\to 2^-} \frac{1}{x-2} = -\infty. 3. Vertical asymptote at x=2x=2.

Explain the connection between infinite limits and vertical asymptotes.

If the limit of a function as xx approaches aa is infinite, then x=ax=a is a vertical asymptote.

Why are vertical asymptotes important in calculus?

They indicate points where a function is undefined and help visualize the function's behavior, especially concerning limits.

Why check both left-hand and right-hand limits at potential vertical asymptotes?

To understand how the function behaves on both sides of the asymptote and confirm its existence.

Describe the behavior of f(x)=1xaf(x) = \frac{1}{x-a} near its vertical asymptote.

As xx approaches aa from the right, f(x)f(x) approaches positive infinity. As xx approaches aa from the left, f(x)f(x) approaches negative infinity.

Explain why ln(x)ln(x) has a vertical asymptote at x=0x=0.

Because limx0+ln(x)=\lim_{x\to 0^+} ln(x) = -\infty, and ln(x)ln(x) is undefined for x0x \le 0.

How does factoring help find vertical asymptotes?

Factoring can simplify rational functions, revealing removable discontinuities and true vertical asymptotes.

Explain the difference between a vertical asymptote and a removable discontinuity.

A vertical asymptote occurs where the function approaches infinity, while a removable discontinuity is a hole in the graph that can be 'removed' by redefining the function.

What does the sign of the infinite limit tell you about the function near a vertical asymptote?

A positive infinite limit means the function increases without bound, while a negative infinite limit means it decreases without bound.

Why is it important to simplify a rational function before finding vertical asymptotes?

Simplifying can reveal common factors in the numerator and denominator, which indicate removable discontinuities rather than vertical asymptotes.

Explain how the graph of a function behaves as it approaches a vertical asymptote.

The graph will approach the vertical asymptote very closely, with the y-values either increasing without bound (approaching positive infinity) or decreasing without bound (approaching negative infinity).

What is a vertical asymptote?

A vertical line x=ax=a that a function approaches but never touches; function is unbounded at x=ax=a.

What is a discontinuity?

A point where a function is undefined or behaves erratically.

What are infinite limits?

Limits that evaluate to either positive or negative infinity.

What does it mean for a function to be unbounded?

The function's value grows or shrinks without any bound, approaching infinity or negative infinity.

What is the relationship between vertical asymptotes and discontinuities?

A vertical asymptote is a type of discontinuity where the function is undefined.

Define limxaf(x)=\lim_{x\to a} f(x) = \infty.

As xx approaches aa, the value of f(x)f(x) increases without bound.

Define limxaf(x)=\lim_{x\to a} f(x) = -\infty.

As xx approaches aa, the value of f(x)f(x) decreases without bound.

What is a one-sided limit?

A limit that considers the function's behavior as x approaches a value from either the left or the right.

What does limxa+f(x)\lim_{x\to a^+} f(x) mean?

The limit of f(x)f(x) as xx approaches aa from the right.

What does limxaf(x)\lim_{x\to a^-} f(x) mean?

The limit of f(x)f(x) as xx approaches aa from the left.