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• What is this question used for?
• What does this question assess?
• What does the student have to do?
• How is the question randomised?
• Are there any implementation details that editors should be aware of?

### Feedback

From users who are members of Bill's workspace :

### History

#### Checkpoint description

Describe what's changed since the last checkpoint.

#### Bill Foster3 years, 4 months ago

Gave some feedback: Ready to use

Published this.

#### Bill Foster6 years, 8 months ago

Created this as a copy of Solution curves and Vector fields 2 : dy/dx=y*(x-y).
Vector fields from diff equation draft Bill Foster 19/11/2013 10:23
Solution curves and Vector fields draft Bill Foster 19/11/2013 16:34
Solution curves and Vector fields 1 : dy/dx=sin(x-y) Ready to use Bill Foster 10/04/2017 17:51
Solution curves and Vector fields 2 : dy/dx=y*(x-y) draft Bill Foster 12/01/2016 19:08
Solution curves and Vector fields 2 : $dy/dx=x^2-y^2$ Ready to use Bill Foster 31/03/2017 21:24
Bill's copy of Solution curves and Vector fields 2 : dy/dx=y*(x-y) draft Bill Foster 12/01/2016 19:15
Solution curves and Vector fields 3: $dy/dx=x^3-y^3$ draft Bill Foster 31/03/2017 21:36
Solution curves and Vector fields 1 : dy/dx=1-sin(y) draft Bill Foster 14/04/2017 11:51
Solution curves and Vector fields 1 : dy/dx=sin(x)-sin(y) draft Bill Foster 10/04/2017 22:09
Lois's copy of Solution curves and Vector fields 2 : $dy/dx=x^2-y^2$ draft Lois Rollings 14/09/2017 15:59
Timur's copy of Solution curves and Vector fields 1 : dy/dx=1-sin(y) draft Timur Zaripov 27/11/2019 07:53
Solution curves and Vector fields 2 : $dy/dx=x^2-y^2$ draft Sid Gurjar 06/04/2020 04:29
Slope_Fields_01 draft Paul Hancock 21/05/2020 06:38

Give any introductory information the student needs.

No variables have been defined in this question.

(a number)

Numbers between and (inclusive) with step size
A random number between and (inclusive) with step size

(text string)

(numbers)

(text strings)

This variable is an HTML node. HTML nodes can not be relied upon to work correctly when resuming a session - for example, attached event callbacks will be lost, and mathematical notation will likely also break.

If this causes problems, try to create HTML nodes where you use them in content areas, instead of storing them in variables.

Describe what this variable represents, and list any assumptions made about its value.

This variable doesn't seem to be used anywhere.

Name Type Generated Value

#### Error in variable testing condition

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Error:

for seconds

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The correct answer is an equation. Use the accuracy tab to generate variable values satisfying this equation so it can be marked accurately.

#### Checking accuracy

Define the range of points over which the student's answer will be compared with the correct answer, and the method used to compare them.

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Give expressions which produce values for each of the variables in the expected answer. Leave blank to pick a random value from the range defined above, following the inferred type of the variable.

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#### Unit tests

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The following tests check that the question is behaving as desired.

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Name Value

 This note produces the expected output

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When you need to change the way this part works beyond the available options, you can write JavaScript code to be executed at the times described below.

Run this script the built-in script.

This script runs after the built-in script.

To account for errors made by the student in earlier calculations, replace question variables with answers to earlier parts.

In order to create a variable replacement, you must define at least one variable and one other part.

The variable replacements you've chosen will cause the following variables to be regenerated each time the student submits an answer to this part:

These variables have some random elements, which means they're not guaranteed to have the same value each time the student submits an answer. You should define new variables to store the random elements, so that they remain the same each time this part is marked.

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• #### Variable replacements

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Variable Value

### Previous parts

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### Parts

#### Steps

Give a worked solution to the whole question.

### Preamble

This script will run after the question's variable have been generated but before the HTML is attached.
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This question is used in the following exam: