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### History and Feedback

#### Checkpoint description

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Published this.

#### Christian Lawson-Perfect2 years, 4 months ago

Gave some feedback: Ready to use

#### Christian Lawson-Perfect2 years, 4 months ago

Saved a checkpoint:

I changed the wording in the advice a bit.

Otherwise, looks good!

#### Bradley Bush2 years, 4 months ago

Gave some feedback: Needs to be tested

#### Bradley Bush2 years, 4 months ago

Thank you for the feedback, I've done pretty much everything you've asked but I am unable to fix the scroller as it is an internet explorer issue. I have also left the last line of e)  because i think it is still a useful piece of extra information and eads nicely onto the nexgt question.

#### Hannah Aldous2 years, 4 months ago

just a few things to comment on:
maybe you could consider changing your title to include a reference to composite functions?
I don't know whether you'd consider a longer statement, maybe explaining what an inverse is and how you find one from an equation/what it might be used for
question d I would maybe separate f(x)...\\and\\g(x)... and then align them
in f you have a comma after c) you either need to remove it or place a comma after your equation
in f typo 'exsist'
with your answer s for f I'm unsure as to whether you need all those full stops as they are not full sentences.
in you advice especially part a it might be nice to have a little explanation as to what you are doing eg what is y
part a of advice is not currently a sentence, maybe you want to expand the first line of both sightly
I'm not sure you need to repeat your questions down in the advice but that is up to you
maybe in advice of d state what g(x) is before you subsitute it
in the advice of e there is a scroller, not sure what it is for and why it is there
not sure you need the last line of e is necessary as it isn't the final solution

#### Hannah Aldous2 years, 4 months ago

Gave some feedback: Has some problems

#### Bradley Bush2 years, 4 months ago

Gave some feedback: Needs to be tested

#### Bradley Bush2 years, 4 months ago

Thank you for the advice, I've acted on those two points, let me know if you think I should make any further alterations.

#### Christian Lawson-Perfect2 years, 4 months ago

Gave some feedback: Has some problems

#### Christian Lawson-Perfect2 years, 4 months ago

Use \left( and \right) around fractions to make sure the brackets stretch to the correct height.

In the advice for the final part, I would use an identity symbol ($\equiv$), and maybe preface the identity with "it is always true that"

#### Bradley Bush2 years, 5 months ago

I've done that simplification

#### Vicky Hall2 years, 5 months ago

If your expression is $\displaystyle\frac{\frac{(x-a)}{b}+c}{bd}$, rearrange it to $\displaystyle\frac{x-a+bc}{bd}$. Type this into the marking box as

(x+{-a+b*c})/{b*d} and it should simplify nicely.

#### Bradley Bush2 years, 5 months ago

Gave some feedback: Needs to be tested

#### Vicky Hall2 years, 5 months ago

Gave some feedback: Has some problems

#### Vicky Hall2 years, 5 months ago

The expected answers are not simplifed here. For example, I entered $\displaystyle \frac{x+6}{10}$ (which was marked as correct) but the expected answer displayed as $\displaystyle \frac{\frac{x-2}{2}+4}{5}$. This is the same in the advice, except here the answer displays as $\displaystyle ((x-2)/2+4)/5$, which is a nightmare to read! Have the advice display the solution in its simplest form and use \frac.

#### Bradley Bush2 years, 5 months ago

Gave some feedback: Needs to be tested

#### Bradley Bush2 years, 5 months ago

Created this.
Patrick's copy of Inverse and composite functions draft Patrick Joyce 27/07/2017 15:58
Inverse functions draft Breanne Chryst 09/08/2017 12:03
Inverse and composite functions draft Matthew Mears 26/09/2017 15:05
Lois's copy of Inverse and composite functions draft Lois Rollings 22/10/2017 11:21
Inverse and composite functions [L3] draft Abbi Mullins 24/07/2018 14:02
Inverse and composite functions draft Matthew Mears 01/10/2018 17:13
Maria's copy of Inverse and composite functions draft Maria Aneiros 25/05/2019 07:26
Inverse and composite functions draft Xiaodan Leng 11/07/2019 01:46

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