# HELM

During the summer of 2020, we started to convert the HELM workbooks into STACK quizzes. The ultimate goal is to create and release one quiz for each of the .pdf workbooks.

To help question authors work in parallel and yet achieve a consistent style we introduced the following style conventions which are now available to any STACK question.

### Key points

• These appear in boxes in the original HELM workbooks.
• Do not include the numbers that appear in the PDFs (i.e. use "Key Point" rather than "Key Point 1")
Example Code

A generalisation of the third law of indices states:

#### Key Point

For all ... .

<p>A generalisation of the third law of indices states:</p>
<div class="HELM_keypoint">
<h4>Key Point</h4>
<p>For all ... .</p>
</div>

### Examples

• Have a horizontal rule before them. They also have a horizontal rule after them, unless they are last in the text.
• Do not include the numbers that appear in the PDFs (i.e. use "Example" rather than "Example 1")
• The headings are <h4> with a special class applied to them for styling.
• Use the HELM_parts and HELM_parts_inline styles to label lists of parts (a), (b), (c), etc.
Example Code

#### Example

Use a calculator to evaluate ... .

#### Solution

Using the ... button on the calculator check that you obtain ... .

<hr>
<h4 class="HELM_example">Example</h4>
<p>Use a calculator to evaluate ... .</p>
<h4 class="HELM_solution">Solution</h4>
<p>Using the ... button on the calculator check that you obtain ... .</p>

#### Example

Identify the index and base in the following expressions.

1. Ex 1.
2. Ex 2.
3. Ex 3.

#### Solution

1. In the expression ..., 8 is the base and 11 is the index.
2. In the expression ..., -2 is the base and 5 is the index.
3. In the expression ..., p is the base and -q is the index.

The interpretation of a negative index will be given in sub-section 4 which starts on page 31.

<hr>
<h4 class="HELM_example">Example</h4>
<p>Identify the index and base in the following expressions. </p>
<ol class="HELM_parts_inline">
<li> Ex 1. </li>
<li> Ex 2. </li>
<li> Ex 3. </li>
</ol>

<h4 class="HELM_solution">Solution</h4>
<ol class="HELM_parts">
<li>In the expression ..., 8 is the base and 11 is the index.</li>
<li>In the expression ..., -2 is the base and 5 is the index.</li>
<li>In the expression ..., p is the base and -q is the index.<p>
</p><p>The interpretation of a negative index will be given
in sub-section 4 which starts on page 31.</p></li>
</ol>

Hint: If <hr> doesn't work try preceding it with <p>&nbsp;</p>.

### Questions

• Start with heading "Exercise" - see below for styling. Note that these are numbered in the PDFs but do not copy the numbers. The Moodle quiz will take care of numbering the questions.
Example Code

Exercise

 <p class="HELM_exercise">Exercise</p>