title: Unused argument in R
body: <p>I am using R Studio and creating some vectors and doing some calculations with them. However, when I execute the code, I get the <code>unused argument</code> error. How can I solve this issue?</p>
  
  <pre><code>f &lt;- c(2,4,6) 
  v &lt;- c(1,2,3,4,5)
  cos(c(0, pi/4, pi/2, pi))
  </code></pre>
  
  <p><img src="https://i.stack.imgur.com/X4Ktg.png" alt="Error"></p>