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Study.com
study.com › skill › learn › how-to-find-the-intercepts-asymptotes-domain-range-from-the-graph-of-a-rational-function-explanation.html
How to Find the Intercepts, Asymptotes, Domain, & Range from the Graph of a Rational Function | Precalculus | Study.com
To write the domain in interval notation, we need to use three intervals and use the vertical asymptotes for endpoints of the intervals. Domain: {eq}(-\infty, -2)\cup (-2, 1)\cup (1,\infty) {/eq} Step 5: Determine the range by looking at the ...
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Wyzant
wyzant.com › resources › ask an expert
How to find Domain, Range and Asymptote? | Wyzant Ask An Expert
September 19, 2018 - Then, the Domain is the set of real number, but 6 exclusive. Now, for range, it "seems" like y can be any real numbers, but if you multiply with (x-6) to both sides, you get · y(x-6) = 2x-6. If y was 2, the left side would be 2x-12 = 2x-6 which is absurdly wrong and no solution, meaning y can't be 2, but any other real numbers. Therefore, the Range is the set of real numbers, 2 exclusive. Asymptotes are basically a point where the graph would approach closer and closer, but will never meet the point in any finite distance.
People also ask

How do you find the domain of a rational function in interval notation?
First, find the values of x that make the denominator of the fraction equal to zero. Then, write (-\infty, number) \union (number, \infty). If there are multiple numbers that make the fraction equal to zero, you want to also include an interval between those numbers in order. Let's say the numbers that make the fraction zero are -2, 2 and zero. The domain of this function would be (-\infty, -2) \union (2,0) \union (0, 2) \union (2, \infty)
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study.com
study.com › academy › lesson › analyzing-the-graph-of-a-rational-function-asymptotes-domain-and-range.html
Domain & Range of Rational Functions | Definition & Graph - Lesson ...
How do you find the domain of a rational expression?
To find the domain of a rational function set the denominator to zero and solve for x. Then, write out the answer in either set or interval notation, ensuring to exclude the values of x that make the denominator of the fraction equal zero.
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study.com
study.com › academy › lesson › analyzing-the-graph-of-a-rational-function-asymptotes-domain-and-range.html
Domain & Range of Rational Functions | Definition & Graph - Lesson ...
How do you find the range of a function without graphing?
Finding the range of a rational function is similar to finding the domain of the function but requires a few additional steps. First, interchange values of x and y in the function. For example if the function is y = 1/x, interchanging the values of x and y produces x=1/y. Then, solve the expression for y. In this example, y=1/x. Now, find the domain of the new function. In this case the domain is any x except for zero. Remember that the goal is to find the range of the function so when writing your answer you need to interchange the x and y again, e.g. say y is not zero instead of saying x is
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study.com
study.com › academy › lesson › analyzing-the-graph-of-a-rational-function-asymptotes-domain-and-range.html
Domain & Range of Rational Functions | Definition & Graph - Lesson ...
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Quora
quora.com › Is-there-any-relationship-between-domain-range-and-asymptote
Is there any relationship between domain, range and asymptote? - Quora
Answer: Yes. Oh, you were wondering what the relationship is? Well, we know that the domain of a function is the interval of x-values where the function exists, and the range is the interval of y-values where the function exists. An asymptote is a curve — generally, but not always, a straight ...
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YouTube
youtube.com › mathispower4u
Ex 1: Domain, Range, Asymptotes of a Basic Rational Function Using Translations - YouTube
This video explains how to determine the domain, range, and asymptotes by translating the basic function f(x)=1/x.http://mathispower4u.com
Published   October 8, 2015
Views   17K
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YouTube
youtube.com › the math sorcerer
Finding the Domain, Range, and Asymptotes from a Graph - YouTube
Please Subscribe here, thank you!!! https://goo.gl/JQ8Nys Finding the Domain, Range, and Asymptotes from a Graph
Published   November 23, 2014
Views   24K
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Slideshare
slideshare.net › home › education › domain-range-intercepts-zeros-and-asymptotes-of-rational-function.pptx
Domain-Range-Intercepts-Zeros-and-Asymptotes-of-Rational-Function.pptx
It provides examples of finding: 1) The domain by identifying values that make the denominator equal to zero. 2) The range by changing the function to be in terms of y and solving for y. 3) Vertical asymptotes by making the denominator equal to zero.
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Reddit
reddit.com › r/learnmath › the horizontal asymptote is y = 2, but how can we tell that the range is (2,∞) instead of (-∞,2) or (-∞,2) u (2,∞) without drawing the graph? same, for the vertical asymptote, say x = 1, how do we tell that domain is (-∞,1) u (1,∞) versus (1,∞) or (-∞,1) instead, without the graph?
r/learnmath on Reddit: The horizontal asymptote is y = 2, but how can we tell that the Range is (2,∞) instead of (-∞,2) or (-∞,2) U (2,∞) without drawing the graph? Same, for the Vertical asymptote, say x = 1, how do we tell that Domain is (-∞,1) U (1,∞) versus (1,∞) or (-∞,1) instead, without the graph?
September 1, 2023 -

I do understand what range and domain are. I use the vertical asymptote to get an idea of what the domain is, and I use the Horizontal Asymptote to get an idea of what the range is.

However, suppose two graphs both have H.A of y = 2 but one's range should be (-∞,2) U (2,∞) and the other's should be (2,∞). Take for instance for y = (1/x) + 2 for the former range. How do you know which is which?

For y = (1/x) + 2, I needed to see/imagine the graph first in order to know how I can use 2 to get the range but got stuck with the post function because I could picture it. I'd like to know these ranges without knowing the graph.

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I'm assuming you're talking about rational functions, since in general functions can have all sorts of crazy domains or ranges. I'm also assuming you want what is officially called "natural domain" because technically "the domain" of a function has to be specified as part of its definition. I suggest picking just a couple numbers and testing them as inputs or outputs. Using y = 1/x² + 2 as an example, you know x = 0 is an asymptote, but you're unsure whether (-∞,0) or (0,∞) or both are part of the domain. Try to plug in x = -1. You get y = 1/(-1)² + 2 = -1 + 2, which exists, so (-∞,0) is part of the domain. Try to plug in x = 238 (it's easier to plug in x = 1, but I want to emphasize that you can pick any number > 0 if you want to test (0, ∞)). You get y = 1/238² + 2, which might be hard to write as a decimal without using a calculator but definitely does exist, so (0,∞) is also part of the domain. The full domain of y = 1/x² + 2 is therefore (-∞,0) U (0,∞). For range it's a little harder, but the same idea works. You know y = 2 is an asymptote, but you're unsure whether (-∞,2) or (2,∞) or both are part of the range. Try to get y = 3 as an output (you could try any number > 2, but 3 is the easiest). This would require 1/x² + 2 = 3, so 1/x² = 1, which is totally doable with x = 1 (or with x = -1, but you only need one working input). So (2, ∞) is part of the range. Try to get y = 1 as an output. This would require 1/x² + 2 = 1, so 1/x² = -1, so x² = -1. If you can only use real numbers then having x² be negative is impossible. Therefore (-∞, 2) is not part of the range. The full domain of y = 1/x² + 2 is therefore (2,∞).
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For the domain, you look for all possible inputs for your function. Define the rule, f(x) = (x-2)1/2 and g(x) = 1/(x-2). For f(x), x-2 ≥ 0 since you can’t take an even root of a negative number in ℝ. Thus x ≥ 2. For g(x), if x=2, then we’d be dividing by 0, thus x≠2. Therefore the domain of f is [2,∞) and the domain for g is (-∞,2)∪(2,∞) To find the range of a function, f, you find the domain of its inverse, f-1 (nasty process, but that’s how you do it without a graph). Rinse and repeat
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Cuemath
cuemath.com › calculus › rational-function
Rational Function - Graph, Domain, Range, Asymptotes
Set the denominator of the resultant equation ≠ 0 and solve it for y. Set of all real numbers other than the values of y mentioned in the last step is the range. Example: Find the range of f(x) = (2x + 1) / (3x - 2). ... Let us replace f(x) with y. Then y = (2x + 1) / (3x - 2). Now, we will solve this for x. (3x - 2) y = (2x + 1) 3xy - 2y = 2x + 1 3xy - 2x = 2y + 1 x (3y - 2) = (2y + 1) x = (2y + 1) / (3y - 2) ... A rational function can have three types of asymptotes: horizontal, vertical, and slant asymptotes.
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Quora
quora.com › How-do-you-find-the-domain-and-range-of-an-asymptote-in-an-exponential-function
How to find the domain and range of an asymptote in an exponential function - Quora
Answer: Luckily for us exponential ... extra info in your question. Lines or asymptotes of the vertical type have domain of x=a and range of \R “a” would be the line’s definition....
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House of Math
alpha.houseofmath.com › encyclopedia › functions › theory of functions › fundamentals of functions › how to calculate domain and range in math
How to Calculate Domain and Range in Math
You can write it as · since · a · c is the horizontal asymptote. Example 1 · Robert is on land and throws a rock into the water. The stone follows a path given by the function · f · ( x · ), where · x is the distance from Robert to the stone in the horizontal direction, and · y is the height the stone has above the water at all times. You will learn that the height of the stone follows the function · Find the domain · D · f and the range ·
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Varsity Tutors
varsitytutors.com › home › domain and range of rational functions
Domain and Range of Rational Functions
For f(x)=1/x, the domain excludes x=0 because division by zero is undefined. The range excludes y=0 since 1/x never equals zero. Graphically, there is a vertical asymptote at x=0 and a horizontal asymptote at y=0.
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Cosenzaassociates
cosenzaassociates.com › wp-content › uploads › 2020 › 03 › A.9A-Domain-and-Range-of-Exponential-Functions.pdf pdf
DOMAIN AND RANGE OF EXPONENTIAL FUNCTIONS
The horizontal asymptote is y = 4. STEP 3c · --c-"c)'#(c(c+(!c) c-"c .(-#)(I · The domain of h(x) is all real numbers. The range of h(x) is all real numbers greater than 4, or h(x) > 4. EXAMPLE 2:ȱ ‘Š›—ŽĴȱŽȱ ™ž›Œ‘ŠœŽȱ Šȱ —Ž ȱ ŸŽ‘’Œ•Žǯȱ ...
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Monterey Institute
montereyinstitute.org › courses › DevelopmentalMath › COURSE_TEXT2_RESOURCE › U17_L2_T3_text_final.html
Finding Domain and Range
There is nothing in the function that obviously restricts the range. However, rational functions have asymptotes—lines that the graph will get close to, but never cross or even touch. As you can see in the graph above, the domain restriction provides one asymptote, x = 6.
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Lumen Learning
courses.lumenlearning.com › waymakercollegealgebra › chapter › domain-and-vertical-asymptotes
Domain and Its Effect on Vertical Asymptotes | College Algebra
Note any values that cause the denominator to be zero in this simplified version. These are where the vertical asymptotes occur. Note any restrictions in the domain where asymptotes do not occur.
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Free Math Help Forum
freemathhelp.com › forums › free math help › calculus
please help! domain, range, horizontal asymptote | Free Math Help Forum
June 14, 2009 - i just don't understand it... how do you when to put brackets by the number? how come there is a parenthesis instead of bracket next to the zero? and i don't get the asymptotes either... Click to expand... This should be like algebra or w.e Anyways I believe [ means inclusive and ( means exclusive. So if x is an element of [0, 5) then it means x is greater than or equal to 0 and less than (not equal to) 5. Another way of writing domain/range would be: \(\displaystyle \[\begin{array}{l} D = \{ x|x \in R, - \infty < x < \infty \} \\ R = \{ y|y \in R,0 < y < \infty \} \\ \end{array}\]\)
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Wyzant
wyzant.com › resources › ask an expert
how to identify the vertical, horizontal, domain, and range of each asymptotes | Wyzant Ask An Expert
January 27, 2016 - The Horizontal Asymptote is going to be y = 0. Why? Well, the limit as x→∞ = 0, since as the denominator gets really large, the overall fraction, 1/x, will get really small. And the limit as x→-∞ = 0, since as the denominator gets really large (negative-wise), the overall fraction, 1/x, will again get really small. For the domain, these are the x-values that you can use, so all real numbers except zero: ... For the range, since you have a horizontal asymptote of y=0, which the graph will never cross in this case, the range will be the same:
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Lumen Learning
courses.lumenlearning.com › uvu-combinedalgebra › chapter › 7-1-rational-functions-and-their-graphs
7.1.1: Rational Functions and Their Graphs | Intermediate Algebra
In set notation Domain = [latex]\{x\;|\;x \in \mathbb{R}, x\neq \pm2\}[/latex] The graph has a horizontal asymptote at [latex]y=1[/latex] but this asymptote is crossed by the function just at [latex]x=2.333[/latex] so must be included in the range. There is however a gap in the range values ...
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Wyzant
wyzant.com › resources › ask an expert
Identify the asymptotes, domain, and range of the function. f(x)= 3/ (x + 2) + 1 | Wyzant Ask An Expert
June 14, 2016 - As x goes to infinity our y value approaches one from the top and as x goes to negative infinity our y value approached 1 form the bottom. So it appears that our range is all y-values except 1. Not a graph can cross a horizontal asymptote. How do you know for sure that the graph does not cross a horizontal asymptoe? Just set y = 1 in the original equation and solve for x. If you can solve for x then the graph crosses its horizontal asymptote otherwise it does not. Try this with your equation.
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YouTube
youtube.com › nicole hamilton
Finding the Domain, Range, and Asymptotes of Rational Functions - YouTube
Finding the Domain, Range, and Asymptotes of Rational Functions using multiple methods
Published   January 8, 2018
Views   31K