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Graph transformations? watch

1. Graph has the points (-1,-3) and (3,1)

equation y=f(3-x) is the transformation applied. given that there is a (-x) does this mean that the function to be applied is f(-x) or is it f(x-a)?

Is there an order to determine which function/operation would go first?
2. (Original post by apronedsamurai)
Graph has the points (-1,-3) and (3,1)

equation y=f(3-x) is the transformation applied. given that there is a (-x) does this mean that the function to be applied is f(-x) or is it f(x-a)?

Is there an order to determine which function/operation would go first?
I did not understand this

it might be helpful if you post a photo of the question
3. The diagram shows part of the graph of a function with equation y=f(x).

two points are given (-1,-3) and (3,1).

Which of the following shows the graph with equation y=f(3-x)?

A (-3,4) (1,0)
B (-6,1) (-2,-3)
c (-4,3) (0,-1)
D (-1,1) (3, -3)
4. (Original post by apronedsamurai)
The diagram shows part of the graph of a function with equation y=f(x).

two points are given (-1,-3) and (3,1).

Which of the following shows the graph with equation y=f(3-x)?

A (-3,4) (1,0)
B (-6,1) (-2,-3)
c (-4,3) (0,-1)
D (-1,1) (3, -3)
translation left by 3, reflection in the y axis

(or for mathematical perverts, reflection in the y axis first, translation right by 3)
5. Ok,

(-1,-3) and (3,1).

Translation left by 3, as "a" >0; subtract from X; giving me (-4,-3). and (0,1).

Reflection in Y axis;= multiply x co-ordinates by -1. (4,-3), (0,-1).

So with that working/logic, I specified the answer as C. However, the answer given is B.

Edit; no that is wrong also, because (0,1) would STILL be (0,1).
6. (Original post by apronedsamurai)
Ok,

(-1,-3) and (3,1).

Translation left by 3, as "a" >0; subtract from X; giving me (-4,-3). and (0,1).

Reflection in Y axis;= multiply x co-ordinates by -1. (4,-3), (0,-1).

So with that working/logic, I specified the answer as C. However, the answer given is B.

Edit; no that is wrong also, because (0,1) would STILL be (0,1).
the points are not there ...

so there is a mistake/typo somewhere in all of this
7. Yes, did it again; and it IS B.

(3,1) Reflection in y axis; so (-3,1). Subtract a; a=3 (-6,1).

(-1,-3) Reflection in y axis; so (1,-3). Subtract a; a=3 (-2,-3).

Reflection has to come first. Doing the y=f(x+a) first; gives you a x value of 0 for (3,1) a>0; ergo, subtract a from x.
8. (Original post by apronedsamurai)
Yes, did it again; and it IS B.

(3,1) Reflection in y axis; so (-3,1). Subtract a; a=3 (-6,1).

(-1,-3) Reflection in y axis; so (1,-3). Subtract a; a=3 (-2,-3).

Reflection has to come first. Doing the y=f(x+a) first; gives you a x value of 0 for (3,1) a>0; ergo, subtract a from x.
well I strongly beg to differ on this

take the point (-1,3)
the line y=-3x satisfies it

now replace x by 3-x
y=-3(3-x)
y=3x-9

NONE of these points is on this line
9. Its about graphs of functions? perhaps that the discrepancy?

Ok, Ive checked with a maths tutor online, it IS B. The method I used was entirely proper.

All I needed to know.
10. (Original post by apronedsamurai)
Its about graphs of functions? perhaps that the discrepancy?

Ok, Ive checked with a maths tutor online, it IS B. The method I used was entirely proper.

All I needed to know.
.....

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