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Published this.

#### Christian Lawson-Perfect3 years, 2 months ago

Gave some feedback: Ready to use

#### Christian Lawson-Perfect3 years, 2 months ago

Saved a checkpoint:

Good question!

It seems you didn't know about display mode maths while writing the advice: enclose maths in $ and $ instead of dollar signs to place it at the centre of its own line with a good margin.

#### Lauren Richards3 years, 2 months ago

Gave some feedback: Needs to be tested

#### Vicky Hall3 years, 2 months ago

I've fixed the variables so that part e) will simplify if it needs to in the advice. I also changed the variables slightly in part b) to avoid ever having square numbers under the roots.

#### Lauren Richards3 years, 2 months ago

I've randomised parts e) and f) now too but having problems with getting e) to finally simplify. Vicky would you mind having a look at this please? I've written THIS NEEDS TO SIMPLIFY next to the issue!

As a result of not getting it simplified, I haven't set the correct answers yet.

#### Lauren Richards3 years, 3 months ago

Gave some feedback: Has some problems

#### Lauren Richards3 years, 3 months ago

I've randomised parts a) to d).

#### Lauren Richards3 years, 3 months ago

Gave some feedback: Needs to be tested

#### Aiden McCall3 years, 3 months ago

a) The advice for part a does not match the question. You could also possibly show another method of multiplying by the denominator to realise the bottom; I could be overcomplicating it with this alternative method, so it is up to you.
b) I would put the 12 in '12 is the denominator' in math mode. Not sure what the last line means I think it is suppose to read $\frac{\sqrt{ab}}{1}$ but reads as $\frac{\sqrt{ab}}{[1,1,1,1,1]}$.
c) Is good
d) There could be some confusing with the wording, "this is the denominator with a changed sign." It could be interpretted as the whole denominator changing signs; I would possibly change it to the rational term sign changed, or something to that effect.

#### Aiden McCall3 years, 3 months ago

a) On my first attempt of the question, I had received the same question for parts i) & ii). This can be fixed with except in your random variables so the same two values do not occur.

b) Everything fine.

c) I'm not sure if you need a semi-colon if you have an 'and' as this does not create two main clauses. When testing this question it always came up as the same values also. It would be more beneficial for someone practising to have a randomising example everytime.

#### Lauren Richards3 years, 3 months ago

Gave some feedback: Needs to be tested

#### Lauren Richards3 years, 3 months ago

Created this.
Rationalising the denominator - surds Ready to use Lauren Richards 20/11/2019 14:41
Simon's copy of Rationalising the denominator - surds draft Simon Thomas 06/06/2019 11:00
Rationalising the denominator - surds draft Laure Helme-Guizon 13/01/2020 05:32
ibrahim's copy of Rationalising the denominator - surds draft ibrahim khatib 10/02/2020 15:40
Rationalising the denominator - surds draft Sid Gurjar 06/04/2020 04:18
Ulrich's copy of Rationalising the denominator - surds draft Ulrich Görtz 16/09/2020 12:24

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