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Example Question #1 :How To Find Domain And Range Of The Inverse Of A Relation
What is the range of the functiony=x2+ 2?
{–2, 2}
all real numbers
undefined
{2}
y≥ 2
y≥ 2
The range of a function is the set ofy-values that a function can take. First let's find the domain. The domain is the set ofx-values that the function can take. Here the domain is all real numbers because nox-value will make this function undefined. (Dividing by 0 is an example of an operation that would make the function undefined.)
So if any value ofxcan be plugged intoy=x2+ 2, canytake any value also? Not quite! The smallest value thatycan ever be is 2. No matter what value ofxis plugged in,y=x2+ 2 will never produce a number less than 2. Therefore the range isy≥ 2.
Example Question #1 :How To Find Domain And Range Of The Inverse Of A Relation
Which of the following values ofxis not in the domain of the functiony= (2x –1) / (x2– 6x+ 9) ?
1/2
0
2
–1/2
3
3
Values ofxthat make the denominator equal zero are not included in the domain. The denominator can be simplified to (x –3)2, so the value that makes it zero is 3.
Example Question #2 :How To Find Domain And Range Of The Inverse Of A Relation
Given the relation below:
{(1, 2), (3, 4), (5, 6), (7, 8)}
Find the range of the inverse of the relation.
The domain of a relation is the same as the range of the inverse of the relation. In other words, the x-values of the relation are the y-values of the inverse.
Example Question #3 :How To Find Domain And Range Of The Inverse Of A Relation
What is the range of the functiony=x2+ 2?
undefined
all real numbers
{–2, 2}
y≥ 2
{2}
y≥ 2
The range of a function is the set ofy-values that a function can take. First let's find the domain. The domain is the set ofx-values that the function can take. Here the domain is all real numbers because nox-value will make this function undefined. (Dividing by 0 is an example of an operation that would make the function undefined.)
So if any value ofxcan be plugged intoy=x2+ 2, canytake any value also? Not quite! The smallest value thatycan ever be is 2. No matter what value ofxis plugged in,y=x2+ 2 will never produce a number less than 2. Therefore the range isy≥ 2.
Example Question #1 :How To Find Domain And Range Of The Inverse Of A Relation
What is the smallest value that belongs to the range of the function?
We need to be careful here not to confuse the domain and range of a function. The problem specifically concerns the range of the function, which is the set of possible numbers of. It can be helpful to think of the range as all the possible y-values we could have on the points on the graph of.
Notice thathasin its equation. Whenever we have an absolute value of some quantity, the result will always be equal to or greater than zero. In other words, |4-x|0. We are asked to find the smallest value in the range of, so let's consider the smallest value of, which would have to be zero. Let's see what would happen toif.
This means that when,. Let's see what happens whengets larger. For example, let's let.
As we can see, asgets larger, so does. We wantto be as small as possible, so we are going to wantto be equal to zero. And, as we already determiend,equalswhen.
The answer is.
Example Question #5 :How To Find Domain And Range Of The Inverse Of A Relation
If, then find
is the same as.
To find the inverse simply exchangeandand solve for.
So we getwhich leads to.
Example Question #1 :How To Find Domain And Range Of The Inverse Of A Relation
If, then which of the following is equal to?
Example Question #2 :How To Find Domain And Range Of The Inverse Of A Relation
Given the relation below, identify the domain of the inverse of the relation.
The inverse of the relation does not exist.
The domain of the inverse of a relation is the same as the range of the original relation. In other words, the y-values of the relation are the x-values of the inverse.
For the original relation, the range is:.
Thus, the domain for the inverse relation will also be.
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