Graphs and Transformations

Question 1

Direct proportion

Answer 1

y=kx

Question 2

Indirect proportion

Answer 2

y=k/x

Question 3

Gen rule about proportionate graphs (irregardless of directness)

Answer 3

It always goes through the origin

Question 4

what is the new thing that you created called?

Answer 4

new image

Question 5

when you tranform the object what do you do to it?

Answer 5

you map it onto the new image.

Question 6

what is a translation?

Answer 6

you move it but you don’t stretch it.

Question 7

what is a reflection?

Answer 7

you flip it on an axis

Question 8

What is a stretch?

Answer 8

You stretch/squish it (elongate and reverse elongation?)

Question 9

With vectors, which of the numbers is which?

Answer 9

The upper one is the horizontal movement, the bottom one is the vertical movement.

Question 10

With these generally can you just give some advice?

Answer 10

the “y” value is f(x) so you can figure out what you need to do to get to that value from it’s new “x”. eg if f(x) then to translate it forward by a you must put in f(x-a) because that number that is equal to that “y” value is a ahead of f(x) and so its equivalent value would be 5 before in terms of x AKA x-a and so to make all the points equivalent it is now f(x-a).

Question 11

f(x) to f(x-a)

Answer 11

translation of (Upper Number) a (Lower Number) 0.

Question 12

f(x) to f(x) + a

Answer 12

translation of (Upper Number) 0 (Lower Number) a.

Question 13

f(x) to -f(x)

Answer 13

reflected in x axis

Question 14

f(x) to f(-x)

Answer 14

reflected in y axis

Question 15

If you stretch parallel to the x axis what is happening?

Answer 15

It’s becoming wider/thinner

Question 16

If you stretch parallel to the y axis what is happening?

Answer 16

It’s becoming taller/shorter

Question 17

f(x) to f(ax)

Answer 17

Stretched parallel to x axis with a scale factor 1/a.

Question 18

f(x) to f(x)a

Answer 18

Stretched parallel to y axis with a scale factor a.