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# y =(fx) ?.... watch

1. can anyone help me with the fx graphs?i kind of understand and i know somebody posted something on it a few days ago...but i cant seem 2 find it
e.g y = fx - 2?

rgrds
2. I'll try, but it's so complicated I'm not100% sure how to do some questions but here are the basic transformations:

y=f(x-a) Translates "a" units to left
y=f(x)-a Translates "a" units down
y=-f(x) Reflects the graph in x axis
y=f(-x) Reflects the graph in y axis
y=f(a-x) Reflects in the line "a/2"
y=f(2x) Stretch in the x axis direction scale factor of 1/2
y=2f(x) Stretch in the y axis direction scale factor 2

Hope that helps!
3. (Original post by Piggy)
I'll try, but it's so complicated I'm not100% sure how to do some questions but here are the basic transformations:

y=f(x-a) Translates "a" units to left
y=f(x)-a Translates "a" units down
y=-f(x) Reflects the graph in x axis
y=f(-x) Reflects the graph in y axis
y=f(a-x) Reflects in the line "a/2"
y=f(2x) Stretch in the x axis direction scale factor of 1/2
y=2f(x) Stretch in the y axis direction scale factor 2

Hope that helps!
Now I'm confused cos I thought that y= f(x-a) translated "a" units to the right (positive direction) because of it being the inverse of what you'd expect......or were you including the negative coefficient of "a" when you said it would go left?
4. (Original post by Gothic pixie)
Now I'm confused cos I thought that y= f(x-a) translated "a" units to the right (positive direction) because of it being the inverse of what you'd expect......or were you including the negative coefficient of "a" when you said it would go left?
That is correct. It moves to the right.
5. For definate:

y=f(x)+a moves graph up if a is positive

y=f(x+a) moves graph right if a<0 and left if a>0

y=-f(x) reflection in x axis

y=f(-x) reflection in y axis

y=af(x) stretch of scale factor a in y direction

y=f(ax) stretch of scale factor 1/a in x direction

Hope it helped!
6. (Original post by Gothic pixie)
Now I'm confused cos I thought that y= f(x-a) translated "a" units to the right (positive direction) because of it being the inverse of what you'd expect......or were you including the negative coefficient of "a" when you said it would go left?
Sorry, my mistake! Doh!
7. No, you didn't make a mistake. It's the inverse. f(x-3) moves 3 to the right, f(x+3) moves 3 to the left.

EDIT: Oh, I see now. I hate the simplification of formulas like that.
8. Haven't you done your non-calculator paper? Surely these should only come up on that...hmm...i hope so anyway cos i don't know it and i've got calculator tomorrow!!

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