ass="hl std">(</span><span class="hl str">&quot;u&quot;</span><span class="hl std">,</span> <span class="hl str">&quot;(-t)&quot;</span><span class="hl std">,</span>
       <span class="hl kwd">gsub</span><span class="hl std">(</span><span class="hl str">&quot;q&quot;</span><span class="hl std">,</span> <span class="hl str">&quot;(-s1)&quot;</span><span class="hl std">, hblend))</span>
<span class="hl std">A0</span>
</pre></div>
<div class="output"><pre class="knitr r">  [1] &quot;(-t)*((-s1) + (-t)*(2*(-s1