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# sketching graphs watch

1. If you have say -ln(2-x) How would you sketch this in terms of translations. Is there any order in terms of which ones you do. I think I'm right in saying inside the bracket first but in this case we have a horizontal translation and a flip in the y axis? Its horizontal translation then a flip in the y then in the x i think but is there a rule for this kind of thing thanks.
2. (Original post by 111davey1)
If you have say -ln(2-x) How would you sketch this in terms of translations. Is there any order in terms of which ones you do. I think I'm right in saying inside the bracket first but in this case we have a horizontal translation and a flip in the y axis?
You need to be a bit careful here.

If you start with (which is a horizontal reflection of the ln graph) then you next need to get to

If you say then .

So is not the correct transformation. Can you see what transformation you need instead?

Then there's one last transformation that I haven't mentioned.
3. (Original post by notnek)
You need to be a bit careful here.

If you start with (which is a horizontal reflection of the ln graph) then you next need to get to

If you say then .

So is not the correct transformation. Can you see what transformation you need instead?

Then there's one last transformation that I haven't mentioned.
I think f(x-2)... so the correct way is to reflect then translate 2 to right
?
4. (Original post by 111davey1)
I think f(x-2)... so the correct way is to reflect then translate 2 to right?
Yes that's right. A very common mistake would be to say it's f(x+2) but you can see that it's not.

There's one last reflection at the end to get -ln(2-x) from ln(2-x).
5. (Original post by notnek)
Yes that's right. A very common mistake would be to say it's f(x+2) but you can see that it's not.

There's one last reflection at the end to get -ln(2-x) from ln(2-x).
Thank you

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