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Maths question

I thought I was supposed to shift this 2 spaces to the left?
Question 2Bi
(edited 7 years ago)
fx.png44.3KB

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Original post by samantham999
I thought I was supposed to shift this 2 spaces to the left?
Question 2Bi


you would move it in the y-direction.
upwards

In general, if we start with y = f(x), then:-
y = f(x) + a translates f(x) 'a' units in the y-direction

if it was y=f(x+a)
y = f(x + a) translates f(x) '-a' units in the x-direction

hope that helps:smile::smile:
Original post by samantham999
Did you do anything with the f(x) = (x-1)(x+2) ?

and thanks for replying x


you would sketch the graph of f(x)=(x-1)(x+2)

then shift it 2 units upwards

try looking at this link

http://www.bbc.co.uk/schools/gcsebitesize/maths/algebra/transformationhirev1.shtml
Original post by samantham999
Is this correct:
y=f(x+2) I translate the curve 2 units to the left?


yes you would move it to the left.and y=f(x-2) to the right
Original post by samantham999
Is this correct:
y=f(x+2) I translate the curve 2 units to the left?


[*]f(x) + a is f(x) shifted upward a units
[*]f(x) – a is f(x) shifted downward a units
[*]f(x + a) is f(x) shifted left a units
[*]f(x – a) is f(x) shifted right a units
Hope that helps:smile:
Original post by maruchan
yes you would move it to the left.and y=f(x-2) to the right


but why am i moving f=(x+2) upwards in 2bi?
Original post by samantham999
but why am i moving f=(x+2) upwards in 2bi?


2bi you would move to the left

2bii you would move upwards
Original post by samantham999
but why am i moving f=(x+2) upwards in 2bi?


is this for C1 or for GCSE?
Original post by maruchan
2bi you would move to the left

2bii you would move upwards


2bi) to -2 n the x axis?
(edited 7 years ago)
Original post by maruchan
is this for C1 or for GCSE?


c1 :frown:
Original post by samantham999
2bi) to -2 right on the x axis?


yes shift 2 places to the left

f(x + a) is f(x) shifted left a units
Original post by maruchan
yes shift 2 places to the left

f(x + a) is f(x) shifted left a units


Thats exactly what I did but in the textbook its wrong, I think I am supposed to use something
Original post by samantham999
c1 :frown:


watch this video it should help

https://www.youtube.com/watch?v=a96TvWBDzpE
Original post by samantham999
Thats exactly what I did but in the textbook its wrong, I think I am supposed to use something


can you show me the textbooks answer
Untitled.png
Original post by maruchan
watch this video it should help

https://www.youtube.com/watch?v=a96TvWBDzpE



the answers:
Original post by samantham999
Untitled.png


the answers:


the textbook may be wrong just follow the video and the rules and then you should get it. you can check your answer on wolphram alpha
Original post by samantham999
I will. I know how to do fx notation with exam solutions but this answer in the textbook doesn't even make sense

did you get an A/A* in maths a level?
i'm doing 6 units this year!! tips?


The textbook is right.
f(x)=(x-1)(x+2) So its a parabola which crosses the x axis at 1 and -2 obviously.

for part one you shift it 2 to the left so now the x intercepts become -4 and -1.

If you don't see how to draw f(x) expand it it may help.
Original post by whydoidothis?
The textbook is right.


I have a feeling it is. can you explain? please
Original post by samantham999
I have a feeling it is. can you explain? please


I explained it ealier on in the thread, just incase you missed it.

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