# f(x) transformations

• Apr 11th 2008, 12:10 PM
romanianxromo
f(x) transformations
Let f(x) = 1/x

Evaluate and plot g(x)= -f(2x) + 1

Start with the innermost transformation and work outward in steps. There are 3 transformations

Wasn't sure how to graph this, or set it up (Crying)
• Apr 11th 2008, 12:14 PM
Moo
Hello,

Well, try this :

- 2x
- f(2x)=1/(2x)
- +1 (it's like translating the graph to the upward as you add 1 to each ordinate)

These are 3 transformations. I dunno if you're asked to show all the steps, but as you know the graph for x and the general behave of 1/x, you should be able to make it.
• Apr 11th 2008, 12:27 PM
romanianxromo
Ok I have graphed f(x)= 1/x

Now with g(x)= -f(2x) +1 does that mean the graph is reflected across the x-axis? If so, then what is the 2 in front of the x. And the 1 is up 1 unit, right?
• Apr 11th 2008, 12:30 PM
Moo
Woops, i forgot the - sign...

Yes, - means that it's reflected across the x-axis.
Then 1/2 means that you divide the ordinates by 2. So it'll give the points at middle way from -1/x and the x-axis. (En gros, tu prends les points à mi-distance entre la courbe -1/x que tu as tracée et l'axe des abscisses, puisqu'à chaque fois tu prends la moitié de l'ordonnée d'un point)

+1 is up 1 yes (puisqu'on ajoute 1 à l'ordonnée de chaque point, c'est comme si on faisait monter la courbe d'une unité)

I hope you really speak French...even in French i'm not sure to be clear :s
• Apr 11th 2008, 12:46 PM
romanianxromo
Ah merci beaucoup! J'suis null en maths mais bon (Headbang)

Je vous remercie bien