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2-1 Relations and functions Pg 55. Relation- is a set of pairs of input and output values. You can write a relation as a set of ordered pairs. (0 ,10), (0.1 , 9.8), (0.2 , 9.4), (0.3 , 8.6), (0.4 , 7.4) Which is input and which is output?. Relations and Functions. Lesson 2-1.
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2-1 Relations and functions Pg 55
Relation- is a set of pairs of input and output values. You can write a relation as a set of ordered pairs. (0 ,10), (0.1 , 9.8), (0.2 , 9.4), (0.3 , 8.6), (0.4 , 7.4) Which is input and which is output?
Relations and Functions Lesson 2-1 Additional Examples Graph the relation {(–3, 3), (2, 2), (–2, –2), (0, 4), (1, –2)}. Graph and label each ordered pair.
Domain of a relation is the set of all inputs, or x- coordinates of the ordered pairs. Range of a relation is the set of all outputs, or y- coordinates of the ordered pairs. Find the domain and range. (2, 4) (3, 4.5) (4, 7.5) (5, 7) (6, 5) (6, 7.5)
Relations and Functions Lesson 2-1 Additional Examples Write the ordered pairs for the relation. Find the domain and range. {(–4, 4), (–3, –2), (–2, 4), (2, –4), (3, 2)} The domain is {–4, –3, –2, 2, 3}. The range is {–4, –2, 2, 4}.
Pair the domain elements with the range elements. Relations and Functions Lesson 2-1 Additional Examples Make a mapping diagram for the relation {(–1, 7), (1, 3), (1, 7), (–1, 3)}.
Function- a relation in which each element of the domain is paired with exactly one element in the range.
Relations and Functions Lesson 2-1 Additional Examples Use the vertical-line test to determine whether the graph represents a function. If you move an edge of a ruler from left to right across the graph, keeping the edge vertical as you do so, you see that the edge of the ruler never intersects the graph in more than one point in any position. Therefore, the graph does represent a function.
Use the vertical-line test to determine whether the graph represents a function.
9 1 – 2 9 1 – x c.ƒ(x) = 9 –1 ƒ(2) = = = –9 Relations and Functions Lesson 2-1 Additional Examples Find ƒ(2) for each function. a.ƒ(x) = –x2 + 1 ƒ(2) = –22 + 1 = –4 + 1 = –3 b.ƒ(x) = |3x| ƒ(2) = |3 • 2| = |6| = 6
Homework pg 59 2-28 even Omit 12 & 14