title: Change margin size in cover page
body: <p>I am trying to add a cover page which is already created in a PDF. </p>
  
  <pre><code>```{r echo=FALSE,out.width='8.27in',out.height='11.69in'}
  knitr::include_graphics('CoverPage.pdf')
  ```
  </code></pre>
  
  <p>I want to change the margins of the <em>first page</em> only. Can you please help me with this?</p>
  
  <p>The following was tried but it changes the margin of the whole document:</p>
  
  <pre><code>geometry: "left=3cm,right=3cm,top=2cm,bottom=2cm"
  </code></pre>