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===Use of equals-sign and absolute value bars===
The equals sign, =, and bar, |, are used as syntax by the wiki template system. Therefore, if a single equals-sign ("=") is used, it will fail to render, instead showing "<nowiki>{{{1}}}</nowiki>". For example, the following template-coding would be invalid:

<pre>{{math|1 + 2 = 3}}</pre>
: produces: {{math|1 + 2 = 3}}, which is invalid code

To resolve this, either: (a) Start the formula with "<code>1=</code>" as in:
<pre>{{math|1=1 + 2 = 3}}</pre>
: produces: {{math|1=1 + 2 = 3}}, or else, (b) enclose the equals-sign in double-braces <nowiki>"{{=}}"</nowiki> as in:
<pre>{{math|1 + 2 {{=}} 3}}</pre>
: produces: {{math|1 + 2 {{=}} 3}}.

A similar difficulty concerns the vertical bars ("|") used to indicate absolute value, which without care would get interpreted as part of the template syntax. The solution is different than for the equals sign: such bars should be entered as "<nowiki>{{!}}</nowiki>":
<pre>{{math|{{!}}''f''(''x'') − ''a''{{!}} < ε}}</pre>
: produces: {{math|{{!}}''f''(''x'') − ''a''{{!}} < ε}}.

This example can also be produced by the following:
<pre><nowiki>{{math|{{mabs|''f''(''x'') − ''a''}} < ε}}</nowiki></pre>
: produces: {{math|{{mabs|''f''(''x'') − ''a''}} < ε}}