Horizontal And Vertical Graph Stretches and Compressions Part 2 of 3

[MintedCoin]

this is so amazing. i get it now!! ahh thanks so much~ but where is part 3? i cant find it!

[patrickJMT]

@MintedCoin that is a good question... i actually do not think i made it

[klodya3]

@patrickJMT Yes you did. You titled it "Graph Transformations about the X-axis and Y-axis" :)

[patrickJMT]

@klodya3 thanks! : )

[pktwin0w1]

My math teacher disliked this..:P

[patrickJMT]

@pktwin0w1 to each, their own!

[heatherawrful]

thank you so much for these videos :) :)

[TazMania757]

Are you willing to come and teach our school?

[patrickJMT]

@TazMania757 no, no i am not

[SAM46323]

please explain if we by 2x for each value of x

so how is (-2,0) equal -1? in X ?

it should be -4

cz 2*-2=-4

i wait your answer

[funkyboy90000]

Hello Patrick, I was watching your videos on strecthing and compressing graphs and i noticed something.

why do we look at different x and y values on different problems?

for example, when you did y=2f(x) you looked only at how the y values changes

but when you did a problem such as y=f(2x) you now looked at how the x values changes

the parenthesis seems very important. what am i missing?

Thanks

[crazyhugs]

Dude.... Thank you.

[abisanthy]

THANK YOU !

learned and understood a lot more from you than from my teacher ! (:

[Romania007]

Hi i was just wondering if i should always compress or stretch a function by a factor of two???

[patrickJMT]

@Romania007 well, that is a pretty vague question. my answer would be: no

[AMERICANchristopher]

the third video is titled: "graph transformations about the x-axis and y-axis"

it just doesn't have a part 3 in the title.

[MaberuKiia]

thanxs a lOt! :)

[MrGinoboy]

Just to clarify, your basically factoring out a 2 from the x coordinate in the first example.

Btw wheres part 3 :P?

[rodrainbow6]

I like this video.. It shortened my learning curve but where is the part 3??

[patrickJMT]

@rodrainbow6 that is a good question

[pateto2007]

thanks you so much for your videos! I'm taking college algebra online and my textbook sucks totally! I can get it only thanks to your great explanations ! Big Thanks :))

[RyanxTran]

This helped so much. I've learned more in parts 1 and 2 than I have in my 4 1/2 months with my math teacher.

[patrickJMT]

@RyanxTran glad to be able to help!

[dkat16]

You just managed to teach me in 7 minutes what I couldn't understand in 7 months. Thank you SO much for these videos. You are truly amazing.

[choppy7272]

" that's the basic idea "

[frangracy]

Hey Patrick, thank you so much for all of your videos, you make math so easy to understand and fun to do... I was just wondering if you have part 3 of this video (Horizontal And Vertical Graph Stretches and Compressions )... Thank you

[MRDTMEDIA]

@frangracy It's called Graph Transformations about the X-axis and Y-axis

[anthonychemistry]

for some reason, it is not allowing me to view the this video......argggggggghhhhh..i will try another pc

[mathdoris]

My only complaint about this video is how you define your horizontal compression/stretchs.

f(cx) is a horizontal compression by 1/c and f(1/c) is a horizontal stretch by c

When he says f(2x) that means a horizontal compression by 1/2

When he says f(1/2x) that means a horizontal stretch by 2

Stretches are always BY a number bigger than 1. Compression are always BY a number between 0 and 1

[arsevela33]

correction... for the graph y=f(2x) u are not multiplying by the x-values, u are dividing by them..example (-4,1) ur new point would be (-2,1)...

[prriincess13]

i dont get from 1:51...

[askabazka]

well, he didn't really mentioned it but what you do when you do y=f(2x) what you're doing is basically multiplying the x-coordinates by 2's reciprocal. so the reciprocal of 2 is 1/2 that is why he says the graph is compressing because you are multiplying by its reciprocal. Vice versa with y=f(1/2x). you are just multiplying all x-coordinates by the reciprocal of 1/2 which is 2.

[Raymondlk]

So can you think about it as dividing the x coordinate by the factor?

X coordinate of -4 divided by 2 = -2(the new x coordinate in your first example)

[Asima817]

Ahhh thanks!  This helps for my test tonight!

[omaro34]

@Asima817

this guy sucks

[omaro34]

@Asima817

[loik345]

good stuff

[chris65]

I was absent for a day at school because I was sick and was completely lost. I have a test tomorrow and I finally get it! Thanks a ton!!!

[CreepyEyeStudios]

Thank you soooo much!!!!

[marniemarie1]

makes the whole thing so much clearer! test tomorrow on this -- might have a chance now :P thanks so much!

[FaiththeHairstylist]

For the first example, it seems like you are multiplying by the reciprocal of 2...

[patrickJMT]

yes, that is what basically happens.

if you see f (cx), you can basically multiply each x-coordinate on the original graph by 1/c, leave the y-coordinate alone, and that will give you a new point on the 'transformed' graph

[aseemkid]

OMGG YOU ARE THE BEST!!! This really helped me it was exactly what i needed for my math assignment and now i am DONE well almost still need to watch the 3 video :P but yeaaa u are a great help keep posting videosss!!!@@@### =P

[Noble1Mitchell]

This is an awesome tutorial! This helped out with a project. I was really unsure about vertical and horizontal compressions and expansions.

[eyeWryst]

Hi! Your videos are great - I'm learning a ton :)

Question to your y= f(1/2x) ex., how would you graph a function like, y= f(1/x+3) ??? In the above ex. you multiply 2 by the x coordinate. But in this function there is no value given for 'x' - y= f(1/x+3)

[BubbleTeasez]

wow all these examples are the exact ones in my hwk xD

[afgsabrina07]

The graph of y=f(1/2x) how come it is stretched by a factor of 2 instead of 1/2?

[patrickJMT]

well, the 'intuitive' idea is that since you are halving the inputs (that is, you are picking an x coordinate, and dividing by 2), so to get to the same 'original x value' (and so the corresponding y-coordinate) you would have to go out twice as far, thus stretching the graph horizontally by a factor of 2.

i recommend graphing y = (x ) ^ 2 and also y = ( 2x ) ^ 2 by plotting points to see this idea!!

[zikafus]

Love the videos.... I caught one little mistake; at 5:25 you say "the x value is going to stay the same" you meant to say "the y value is going to stay the same."

KEEP UP THE GREAT WORK! These help me a TON!

[patrickJMT]

ops! thanks for pointing out the mistake. glad it was ok otherwise!