Math Functions, Relations, Domain & RangeBy Ms. R. Scott
In math, a relation is just a set of ordered pairs Note: { } are the symbol for "set" Some Examples of Relations include { (0,1) , (55,22), (3,-50) } { (0, 1) , (5, 2), (-3, 9) } { (-1,7) , (1, 7), (33, 7), (32, 7) }
The Domain and Range of a RelationThe domainis the set of all the first numbers of the ordered pairs . In other words, the domain is all of the x-values.
RANGEThe range is the set of the second numbers in each pair, or the y-values.
Examples of the domain and range of a relation. In the relation above the domain is { 0, 3, 90 } And the range is { 1, 22, 34 }
What makes a relation a function in Math? In mathematics, what distinguishes a function from a relation is that each x value in a function has one and only ONE y-value. Some people find it helpful to think of the domain and range as people in romantic relationships. If each number in the domainis a person and each number in therangeis a different person, then a function is when all of the people in the domain have 1 and only 1 boyfriend/girlfriend in the range.
Compare the two relations on the belowSince relation #1 has ONLY ONE y value for each x value, this relation is a function. On the other hand, relation #2 has TWO distinct y values '2'  and '4' for the same x value of '1'. Therefore, relation #2 does not satisfy the definition of a mathematical function.
Evaluating Functions in math To evaluate a function, we insert a given x value, a number in the domain, and see what number we get, which is a number in a range.  Some examples: f(x)  = 2x To evaluate f(4)           f(4) = 2(4) = 8 We just evaluated f(x) for the value x = 4.
The Vertical Line Test The vertical Line test is a wy to determine whether or not a relation is a function. The vertical line test simply states that if a vertical line intersects the relation's graph in more than one place, then the relation is a NOT a function. Relation #2 does not pass the vertical line test.
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Math functions, relations, domain & range
Math functions, relations, domain & range
Math functions, relations, domain & range

Math functions, relations, domain & range

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    Math Functions, Relations,Domain & RangeBy Ms. R. Scott
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    In math, arelation is just a set of ordered pairs Note: { } are the symbol for "set" Some Examples of Relations include { (0,1) , (55,22), (3,-50) } { (0, 1) , (5, 2), (-3, 9) } { (-1,7) , (1, 7), (33, 7), (32, 7) }
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    The Domain andRange of a RelationThe domainis the set of all the first numbers of the ordered pairs . In other words, the domain is all of the x-values.
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    RANGEThe range isthe set of the second numbers in each pair, or the y-values.
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    Examples of thedomain and range of a relation. In the relation above the domain is { 0, 3, 90 } And the range is { 1, 22, 34 }
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    What makes arelation a function in Math? In mathematics, what distinguishes a function from a relation is that each x value in a function has one and only ONE y-value. Some people find it helpful to think of the domain and range as people in romantic relationships. If each number in the domainis a person and each number in therangeis a different person, then a function is when all of the people in the domain have 1 and only 1 boyfriend/girlfriend in the range.
  • 7.
    Compare the tworelations on the belowSince relation #1 has ONLY ONE y value for each x value, this relation is a function. On the other hand, relation #2 has TWO distinct y values '2'  and '4' for the same x value of '1'. Therefore, relation #2 does not satisfy the definition of a mathematical function.
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    Evaluating Functions inmath To evaluate a function, we insert a given x value, a number in the domain, and see what number we get, which is a number in a range.  Some examples: f(x)  = 2x To evaluate f(4)   f(4) = 2(4) = 8 We just evaluated f(x) for the value x = 4.
  • 9.
    The Vertical LineTest The vertical Line test is a wy to determine whether or not a relation is a function. The vertical line test simply states that if a vertical line intersects the relation's graph in more than one place, then the relation is a NOT a function. Relation #2 does not pass the vertical line test.
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