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# Graphs of transformation ques watch

1. Hello, I don't fully understand this transformation. I understand why the graph goes through 2 & -2. However, I don't understand how they got the Y coordinate as -4 . The sketch in part a) is the graph they want translated btw.
Attached Images

2. Also, in the second picture, they moved the graph over by 2, I thought when translate f(x) + 4 it will only affect the graph vertically and I can see that as it goes through 4. But the graph moves left by 2
3. (Original post by animemaniac132)
Hello, I don't fully understand this transformation. I understand why the graph goes through 2 & -2. However, I don't understand how they got the Y coordinate as -4 . The sketch in part a) is the graph they want translated btw.
In the equation you could substitute x for x+2, giving (x+2)(x-2), so when x = 0 y = -4.

Or you could differentiate the original graph, notice that the minimum is at x = 2, y = -4 and then you just shift that co-ordinate as well.
4. (Original post by animemaniac132)
Also, in the second picture, they moved the graph over by 2, I thought when translate f(x) + 4 it will only affect the graph vertically and I can see that as it goes through 4. But the graph moves left by 2
They're not dealing with f(x) +4 in this question.
5. (Original post by animemaniac132)
Hello, I don't fully understand this transformation. I understand why the graph goes through 2 & -2. However, I don't understand how they got the Y coordinate as -4 . The sketch in part a) is the graph they want translated btw.
(Original post by animemaniac132)
Also, in the second picture, they moved the graph over by 2, I thought when translate f(x) + 4 it will only affect the graph vertically and I can see that as it goes through 4. But the graph moves left by 2
the curve y = f(x) has equation y = x(x-4)

y=f(x+2) = (x + 2) (( x + 2) -4) = (x + 2)(x - 2)

when x = 0 y =-4

in the second picture I have no idea what seems to be the problem
the transformation is translation UP by 4
and that is what they did
6. TeeEm
SeanFM

I slightly get it now.. for part c, I can see that if you expand the brackets for the original equation and add on 4 you'll get

For part b, I'm still unsure why you subtracted 4 teeEM
7. (Original post by animemaniac132)
TeeEm
SeanFM

I slightly get it now.. for part c, I can see that if you expand the brackets for the original equation and add on 4 you'll get

For part b, I'm still unsure why you subtracted 4 teeEM
Ah, I see that you had a second image..

Remember that f(x) = x(x-4), so substituting in x+2 whenever there is an x gives (x+2)((x+2)-4).

For these questions you can find the equations of the graphs but I think the idea is to just apply what you know about transformations, and the equations are just to confirm that you've got it right - sometimes you'll just get a graph and some co-ordinates of interest but not the actual equation, so it's better to rely on the first method.
8. ohhhh yes, sorry my brain just starting working again
thanks bud
9. (Original post by animemaniac132)
TeeEm
SeanFM

I slightly get it now.. for part c, I can see that if you expand the brackets for the original equation and add on 4 you'll get

For part b, I'm still unsure why you subtracted 4 teeEM
I did not subtract 4 for part b
10. (Original post by SeanFM)
Ah, I see that you had a second image..

Remember that f(x) = x(x-4), so substituting in x+2 whenever there is an x gives (x+2)((x+2)-4).

For these questions you can find the equations of the graphs but I think the idea is to just apply what you know about transformations, and the equations are just to confirm that you've got it right - sometimes you'll just get a graph and some co-ordinates of interest but not the actual equation, so it's better to rely on the first method.
Yeah, you are right. The past paper questions are very different to questions in the book..

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Updated: November 7, 2015
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