#Graph functions

132 messages · Page 1 of 1 (latest)

fresh cosmos
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it is a reciprocal graph

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it is a transformation of f(x) = 1/x

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the graph f(x) = 1/x has the asimptotes of x = 0 and y = 0

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this one has asimptotes of x = -2 and y = 0

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you can work out the translation using that

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then use that to formulate a function for that graph

eager linden
fresh cosmos
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1/x

eager linden
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but it crosses at 1 on the y axis

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so that cant be the equation

fresh cosmos
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no this is a translation of that graph

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so the equation of this graph is not 1/x

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but a translation of 1/x

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st it is possible for x = 0

eager linden
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basically the quesiton is ur given that graph

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and its called y=f(x)

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and i have yo suggest a possible equation for f(x)

fresh cosmos
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yh

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so by looking at it

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it looks like a reciprocal graph right?

eager linden
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yes

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but the normal reciprocal graphs i see dont cross the y axis

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this one does

fresh cosmos
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yh

eager linden
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and its asymptote is -2

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not 0

fresh cosmos
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yes

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but

eager linden
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well the normal axis

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yh

fresh cosmos
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but

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if you take a graph

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such as

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y = x

eager linden
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yh

fresh cosmos
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then translate it by a vector of (2 0)

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what is its y-intercept gonna be

eager linden
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idk

fresh cosmos
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draw it out

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whats y = x

eager linden
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diagonal line

fresh cosmos
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then draw the translation

eager linden
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across origin

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upwards

fresh cosmos
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yh

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yh

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and is the translation gonna cross the origin?

eager linden
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no

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its gonna cross x axis at -2

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i think

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idk

fresh cosmos
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yes

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so where will it cross the y axis

eager linden
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2?

fresh cosmos
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yh

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ok

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so now

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the same kinda principal applies to the reciprocal graph

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y = 1/x doesnt intercept the y axis

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but that does not mean its translations will also not intercept the y axis

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in fact

fresh cosmos
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dyk why the graph y = 1/x doesnt intercept the y axis?

eager linden
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cause those are its asymptotes

fresh cosmos
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yes but why are they its asymptotes?

eager linden
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the asymptotes are the axes idk

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uh

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no clue

fresh cosmos
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can you do 1/0?

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does that have an actual result or is it undefined?

eager linden
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undefined

fresh cosmos
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yh

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so when x = 0

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will there be a value for y?

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if the graph is y = 1/x

eager linden
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no

fresh cosmos
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exactly

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thats why it doesnt cross the y axis. cause the y axis is the line x = 0

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however it does tend to the line x = 0

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thats just because as the values get smaller what happens to y?

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in terms of how its value differs from consequtive x values

eager linden
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um

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idk

fresh cosmos
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which one is bigger 1/2 or 1/3?

eager linden
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1/2

fresh cosmos
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ok

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and out of these which is bigger: 1/0.1 or 1/0.2?

eager linden
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1/0.1

fresh cosmos
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yh

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why is that?

eager linden
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cause to simplify it

fresh cosmos
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no

eager linden
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u can times it by 10

fresh cosmos
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look at denominators

eager linden
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and so 10/2 = 5

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10/1 = 10

eager linden
fresh cosmos
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without doing any calculations

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u can determine 1/2 is bigger than 1/3

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without converting them to decimals

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because of the denominators

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what is it abt the denominators that makes 1/2 bigger than 1/3?

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think of it like this: if you have more parts of the same whole, each part will be smaller

eager linden
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oh yh that makes sense

fresh cosmos
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hence why as x approaches 0, y approaches infinity

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but x never reaches 0

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because it is impossible

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anyway

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back to the q

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if the asymptotes have changed

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but the shape of the graph remains the same

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what kind of transformation are we looking at?

eager linden
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translation

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x axis moves back 2

fresh cosmos
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yh

eager linden
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so f(x+2)

fresh cosmos
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yes

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now plug that, x + 2, into the function f(x) = 1/x

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what equation do you get?

eager linden
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wait wdym

fresh cosmos
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as in

eager linden
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1/x+2 ?

fresh cosmos
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yes

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so what's your function?

eager linden
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f(x) = 1/x+2

fresh cosmos
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wonderful

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gj

eager linden
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so thats the answer?

fresh cosmos
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yh

eager linden
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ooh okay makes sense now

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thank yu so much

fresh cosmos
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np