Simple inline math
.
$1+1 = 2$
.
<p><span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>1</mn><mo>+</mo><mn>1</mn><mo>=</mo><mn>2</mn></mrow><annotation encoding="application/x-tex">1+1 = 2</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="strut" style="height:0.64444em;"></span><span class="strut bottom" style="height:0.72777em;vertical-align:-0.08333em;"></span><span class="base textstyle uncramped"><span class="mord mathrm">1</span><span class="mbin">+</span><span class="mord mathrm">1</span><span class="mrel">=</span><span class="mord mathrm">2</span></span></span></span></p>
.

Simple block math
.
$$1+1 = 2$$
.
<span class="katex-display"><span class="katex"><span class="katex-mathml"><math><semantics><mrow><mn>1</mn><mo>+</mo><mn>1</mn><mo>=</mo><mn>2</mn></mrow><annotation encoding="application/x-tex">1+1 = 2
</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="strut" style="height:0.64444em;"></span><span class="strut bottom" style="height:0.72777em;vertical-align:-0.08333em;"></span><span class="base displaystyle textstyle uncramped"><span class="mord mathrm">1</span><span class="mbin">+</span><span class="mord mathrm">1</span><span class="mrel">=</span><span class="mord mathrm">2</span></span></span></span></span>
.