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### History and Feedback

#### Checkpoint description

Describe what's changed since the last checkpoint.

#### Mohini Chand1 year, 2 months ago

Gave some feedback: Ready to use

#### Chris Graham2 years, 1 month ago

Gave some feedback: Ready to use

#### Chris Graham2 years, 1 month ago

This question had an unwieldy part b), asking the student to simplify an expression containing many log terms. This was set up in an extraordinarily complicated way with over a dozen variables and, as I'm sure we have other similar questions written in a less complex way, I have removed it and reorganised part a) to become two parts. The question is very straightforward now, but I think that's OK.

Published this.

#### Aiden McCall2 years, 2 months ago

Saved a checkpoint:

Edited some of the advice and added the simplified answer to the advice (with visibility so if gcd of the numerator and denominator = 1 it will only show that and not try to simplify).

#### Hannah Aldous2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Elliott Fletcher2 years, 2 months ago

Gave some feedback: Has some problems

#### Elliott Fletcher2 years, 2 months ago

This looks like a good question i just have a few comments.

In the statement you might need to have a comma after you state the first law of logarithms.

Main Parts

a) good

b) are you wanting the student to input their answer as a simplified fraction or just any fraction? you might need to put in a precision restriction.

a) i) good, just a typo "subsituting" should be "substituting".

a) ii) same typo as in a) i)

I think the have typed up the wrong questions for the advice here, i'm not sure where the a) ii) part fits in

I think the advice for a) iii) is meant to be for question a) ii) but the numbers here aren't the same as in the question.

Also you have two a) iii)s in the advice, but there are only two questions in part a) in the actual question.

b) i) you might need a full stop after the first line of maths here.

b) ii) again you might need a full stop after the first line of maths.

One of the logs here is in italics as well whereas the others aren't.

Also the final answer in the advice here is not given as a simplified fraction.

#### Hannah Aldous2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Chris Graham2 years, 2 months ago

Gave some feedback: Has some problems

#### Chris Graham2 years, 2 months ago

Part b) asks for the answers as a fraction, but the gaps do not accept fraction input. In addition, the correct answer is displayed as a decimal. Tick the "Allow the student to enter a fraction?" checkbox, which will also reveal an option to display the answer as a fraction.

In the advice, rather than (...), use \left( and \right) for parentheses, which scale to the height of the contents.

The pairs (i),(ii) and (iii),(iv) in part a) don't really ask anything different, but I think that's OK. You could have (iv) result in a fraction, though then you will need to add "Enter your answer as a fraction where appropriate" or similar in the part prompt.

Otherwise this is good.

#### Hannah Aldous2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Christian Lawson-Perfect2 years, 2 months ago

Gave some feedback: Has some problems

#### Christian Lawson-Perfect2 years, 2 months ago

Saved a checkpoint:

The gaps should be number entry parts, not mathematical expressions.

#### Hannah Aldous2 years, 2 months ago

Gave some feedback: Needs to be tested

#### Hannah Aldous2 years, 2 months ago

Created this as a copy of Combining Logarithm Rules to Solve Equations.
Combining Logarithm Rules to Solve Equations Ready to use Hannah Aldous 14/08/2017 11:56
Using Laws for Addition and Subtraction of Logarithms Ready to use Hannah Aldous 28/06/2018 01:02
Rearranging Logarithms involving Indices Ready to use Hannah Aldous 01/08/2017 13:52
MATH6058 Addition and Subtraction of Logarithms draft Catherine Palmer 09/10/2017 11:30
Raphael's copy of Rearranging Logarithms involving Indices draft Raphael Stuhlmeier 27/11/2017 16:06
Addition and Subtraction of Logarithms draft Ida Landgärds 16/04/2018 10:43
Ida's copy of Rearranging Logarithms involving Indices Ready to use Ida Landgärds 09/05/2018 06:55
spørsmål 3 draft Ida Landgärds 14/05/2018 10:28
Jonathan's copy of Using Laws for Addition and Subtraction of Logarithms draft Jonathan Kress 07/06/2018 01:10
Jeanne's copy of Using Laws for Addition and Subtraction of Logarithms draft Jeanne Parmentier 20/07/2018 09:31
Using Laws for Addition and Subtraction of Logarithms [L6 Randomised] Needs to be tested Matthew James Sykes 25/07/2018 11:08
Rearranging Logarithms involving Indices [L6] draft Abbi Mullins 24/07/2018 14:39
logarithms addition/subtraction [L6] draft Abbi Mullins 24/07/2018 14:49
NUMBAS-Logarithms (laws) Ready to use Katy Dobson 30/07/2018 10:39
David's copy of Using Laws for Addition and Subtraction of Logarithms Ready to use David Martin 21/09/2018 11:50
David's copy of Combining Logarithm Rules to Solve Equations draft David Martin 30/07/2018 14:34
David's copy of Rearranging Logarithms involving Indices Ready to use David Martin 21/09/2018 11:42
Joël's copy of Using Laws for Addition and Subtraction of Logarithms draft Joël Cohen 27/08/2018 12:12
Blathnaid's copy of spørsmål 3 draft Blathnaid Sheridan 05/10/2018 20:33
Algebra: Using Laws for Addition and Subtraction of Logarithms draft Clare Lundon 15/10/2018 21:45
cormac's copy of Ida's copy of Rearranging Logarithms involving Indices draft cormac breen 05/11/2018 13:37
cormac's copy of Ida's copy of Rearranging Logarithms involving Indices draft cormac breen 05/11/2018 13:38
cormac's copy of Ida's copy of Rearranging Logarithms involving Indices draft cormac breen 05/11/2018 13:54
Max's copy for Addition and Subtraction of Logarithms draft Max S 16/11/2018 23:50
Justin's copy of Using Laws for Addition and Subtraction of Logarithms draft Justin McGuinness 14/05/2019 14:55
Maria's copy of Rearranging Logarithms involving Indices draft Maria Aneiros 11/06/2019 05:32
Maria's copy of Using Laws for Addition and Subtraction of Logarithms draft Maria Aneiros 11/06/2019 05:30
Maria's copy of Combining Logarithm Rules to Solve Equations draft Maria Aneiros 25/05/2019 08:02
Using Laws for Addition and Subtraction of Logarithms draft Xiaodan Leng 10/07/2019 23:28
Logarithms (laws) draft Xiaodan Leng 10/07/2019 23:57
Using Laws for Addition and Subtraction of Logarithms draft Xiaodan Leng 11/07/2019 00:00
Addition and Subtraction of Logarithms draft Xiaodan Leng 11/07/2019 00:15
Rearranging Logarithms involving Indices draft Xiaodan Leng 11/07/2019 00:16
Combining Logarithm Rules to Solve Equations draft Xiaodan Leng 11/07/2019 01:39
Katy's copy of NUMBAS-Logarithms (laws) draft Katy Dobson 03/09/2019 08:37
Katy's copy of Combining Logarithm Rules to Solve Equations draft Katy Dobson 03/09/2019 08:29
Katy's copy of Using Laws for Addition and Subtraction of Logarithms draft Katy Dobson 03/09/2019 08:29
Katy's copy of Rearranging Logarithms involving Indices draft Katy Dobson 03/09/2019 08:49

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