Transformation

[dinosaur93]

The graph of y = g(x) is attached to this post. The transformation in which will NOT change the y-intercept is
a. y = 2g(x)
b. y = -2g(x)
c. y = g^-1 (x)
d. y = g(- x)

How was the answer D

[b^3]

The graph of y = g(x) is attached to this post. The transformation in which will NOT change the y-intercept is
a. y = 2g(x)
b. y = -2g(x)
c. y = g^-1 (x)
d. y = g(- x)

How was the answer D

D flips g(x) in the y-axis, so the left side of the graph becomes the right and the right side of the graph becomes left. But since it is flipped in the y-axis, the y-intercept will be the same.

EDIT: Working if you want it
-x'=x, y'=y
x'=-x
(x,y)->(x',y')
(x,y)->(-x,y)
That means it is flipped in the y-axis.

[monkeywantsabanana]

g(-x) is a reflection in the y-axis. Think about what happens if you reflect it along the y-axis.

[dinosaur93]

i see.... tnx guys!

so a. is definitely wrong as it is dilated
b. can't be because it is reflected in the x-axis....yeah?
how about c., could anyone help me graph it to see is difference from the rest?

[b^3]

i see.... tnx guys!

so a. is definitely wrong as it is dilated
b. can't be because it is reflected in the x-axis....yeah?
how about c., could anyone help me graph it to see is difference from the rest?

C is the inverse, so it is reflected in the line y=x. So already (unless it is a fluke) the y-intercept will change, it will become -1 or 5.

EDIT: Fixed wording.

[HERculina]

I was thinking looking at the straight line in the graph the equation for that would be y= x + 1 so even if u change the x part (ie making it negative) the c part/ y - intercept of the equation would be the same like when you make x=O. It would still be 1. And All the other options would change the graph

[Lasercookie]

I was thinking looking at the straight line in the graph the equation for that would be y= x + 1 so even if u change the x part (ie making it negative) the c part/ y - intercept of the equation would be the same like when you make x=O. It would still be 1. And All the other options would change the graph

y = x + 1
inverse: x = y + 1
rearrange for y:
y = x - 1

The y-int of the inverse function is (0,-1).

I poorly graphed the inverse using ms-paint:


I'm not too sure on the (0, 5) part though, is it actually touching the line on the original graph at what looks to be (0,5)? I guess that's why we normally have those open or closed ended circles at the endpoints on graphs. (note that the circles I put on that graph are just showing y-intercepts). 

[b^3]

Yeh I think it's touching (0,5) so it will become (5,0).

Also if your using chrome (and I'm sure Firefox will have an equivalent) you can get a chrome extenstion thats basically a graphing calculator. I look for the link and edit it back in here.

[b^3]

Also note for the inverse you would have to restrict it to be a one to one function, so only one arm would be chosen, depending on which side you pick.

EDIT: The extenstion I was talking about -> https://chrome.google.com/webstore/detail/bhdheahnajobgndecdbggfmcojekgdko?hl=en
Or just the webpage -> https://www.desmos.com/calculator/

[dinosaur93]

i see.....tnx guys!

laseredd, How did you manage to show the image without attaching it instead?

[Lasercookie]

laseredd, How did you manage to show the image without attaching it instead?

[img] insert your image url here [img]

There's also a button to insert images with all those little icons above box to type stuff in - next to the pi symbol, the little framed Mona Lisa icon.

I upload images to imgur.com, my computer seems to be a bit dodgy with attaching files on AN - I don't know why.

[dinosaur93]

oh, haha, i see, tnx!