 class="eqno"><eqn><span class="katex-display"><span class="katex"><span class="katex-mathml"><math><semantics><mrow><mi>a</mi><mo>+</mo><mi>b</mi></mrow><annotation encoding="application/x-tex">a+b</annotation></semantics></math></span><span class="katex-html" aria-hidden="true"><span class="strut" style="height:0.69444em;"></span><span class="strut bottom" style="height:0.77777em;vertical-align:-0.08333em;"></span><span class="base displaystyle textstyle uncramped"><span class="mord mathit">a</span><span 