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5 WAYS. to determine if a Relation is a Function. Relation - a set of input values and output values, often written as ordered pairs (where x is input and y is output).
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5 WAYS to determine if a Relation is a Function
Relation- a set of input values and output values, often written as ordered pairs (where x is input and y is output)
Relation- a set of input values and output values, often written as ordered pairs (where x is input and y is output)* NOTevery relation is a function.
Relation - a set of input values and output values, often written as ordered pairs (where x is input and y is output)* NOTevery relation is a function.Function - a rule that assigns each input to exactly oneoutput.
Relation - a set of input values and output values, often written as ordered pairs (where x is input and y is output)* NOTevery relation is a function.Function - a rule that assigns each input to exactly oneoutput. For every x there is one, and only one, y.
Relation - a set of input values and output values, often written as ordered pairs (where x is input and y is output)* NOTevery relation is a function.Function - a rule that assigns each input to exactly oneoutput. For every x there is one, and only one, y.* EVERY function IS a relation.
Function What is the difference in a relation and a function? Relation
There are 5 ways to determine if a Relation is a Function One way is called: Mapping Input Output 2 3 4 4 6 6 8
This mapping shows each input value and its corresponding output value. This is NOT a function. Why? Input Output 2 3 4 4 6 6 8 The input “2” has more than one output.
Is this a function? Input Output 1 2 0 3 Yes, the inputs have only one output.
Another way is called: an X Y Table (T-table) Input Output 2 3 4 6 6 8
Is this a function? x y 0 1 • 3 2 5 Yes, each input has only one output!
Another way is called: Ordered PairsIs this relation a function? (3,1), (5,3), (2,8), (6,8) Yes, each input (x) has only one output (y)! None of the x’s are repeated!
Is this relation a function? (5,8), (3,7), (1,6), (5,4) No, the input 5 has two outputs!
Is this relation a function? (5,8), (3,7), (1,6), (3,7) Yes, the input 3 alone isn’t repeated, the output that goes with it was repeated too. Remember the rule, each input can have only one output. The only output for 3 is 7.
Another way is by graphing and using the Vertical Line TestIs this a function? No, because the input 2 has two outputs. Draw a vertical line to check.
Is this a function? Yes, because each input has only one output. Draw vertical lines to check.
Is this a function? No, because the input, 3, has infinite outputs.
Is this a function? NO, use the vertical line test.
Another way is called a: Function Table: input (x) ⟹ the function rule ⟹ output (y) What is the rule of this function?_________________________________
Function Table: input (x) ⟹ the function rule ⟹ output (y) What is the rule of this function? -3x - 5
Function Table: input (x) ⟹ the function rule ⟹ output (y) What is the rule of this function? -3x - 5 What is happening to x?________________________________________
Function Table: input (x) ⟹ the function rule ⟹ output (y) What is the rule of this function? -3x - 5 What is happening to x? x is being multiplied by -3, then combined with -5
Function Table: input (x) ⟹ the function rule ⟹ output (y) What is the rule of this function? -3x - 5 What is happening to x? x is being multiplied by -3, then combined with -5 How could you write this rule as an equation?______________________
Function Table: input (x) ⟹ the function rule ⟹ output (y) What is the rule of this function? -3x - 5 What is happening to x? x is being multiplied by -3, then combined with -5 How could you write this rule as an equation? y = -3x - 5
Function Table: input (x) ⟹ the function rule ⟹ output (y) This Function Table represents the Function: y = -3x – 5 What is y, if x = - 4 ?
Function Table: input (x) ⟹ the function rule ⟹ output (y) This Function Table represents the Function: y = -3x – 5 What is y, if x = - 4 ? y = 7
Is this a function? y = 4x + 1 Yes, it’s linear, so think about the shape of the graph and the vertical line test! You can also plug values in for x and see what you get for y.