title: mtext() in R plot
body: <p>I was wondering what's wrong with <code>mtext()</code> that I can't get the number <code>G</code> correctly show above my plot?</p>
  
  <p><strong>Here is my R code:</strong></p>
  
  <pre><code>G &lt;- .3333 ## but G can be anything as it comes from a function
  
  curve(dnorm(x),-3,3)
  mtext(expression(paste("Medium: ",bold('CT'[12])," = ", round(G,2))),line=3)
  </code></pre>