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We speak student! Relations and functions a'la shmoop it's friday night

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at mathlete high school the annual dance that everyone has been waiting for is [

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finally here the function stance where you can only use dance moves that [kids dancing in a school hall]

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resemble functions usually students can dance like relations which gives them a

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lot of freedom maybe too much freedom why well because a relation is a set of

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ordered pairs all we need to do to come up with these ordered pairs is relate x [relation function definition and example on a chalkboard]

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and y in some way so during these dances Michael Gaga a distant relative of Lady

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Gaga can get his groove on however he likes the chaperones just sit in the [Michael Gaga dancing at the annual mathlete dance]

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corner and play solitaire on their iPhones but the functions dance is a

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special one unfortunately Michael is in trouble he doesn't know what a function [Michael looking confused at the thought of what a function is]

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is and chaperones crack down on dance moves that don't resemble functions at

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the functions dance Michael hears his favorite song YMCA and starts making

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[Michael raising his arms to make the Y letter] the Y this is a function to see if it's a function we can use the vertical

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line test if any vertical line that's drawn touches the graph at only one

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point it's a function a vertical line drawn through either of the diagonal

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parts of the Y only touch it once but a vertical line drawn straight through the [verticle and diagonal line drawn through a x and y axis]

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center of the Y touches it lord knows how many times not a function now the

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end same deal vertical lines drawn through the slanted part of the letter

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pass the test but the left and right parts of the letter are vertical lines [left and right part of the letter M highlighted green]

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themselves so it's a no-go here as well then the C we are not having good luck

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so far it's pretty clear that a vertical line drawn through just about any part

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of the sea touches the graph more than once so we're still on the lookout for a

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letter that would qualify as a function finally the A nope the left most and [Letter A on a vertical line test graph with blue lines through the letter]

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right most parts of the A pass the test but not this area in the middle okay

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would any letters pass the vertical line test well there aren't many but V works

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the vertical line here vertical line there no matter where you draw it V passes

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the vertical line test now that makes us want to dance [Michael on the floor dancing]

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