title: What causes an unbound variable error in Scheme?
body: <p>I've started out with SICP and I'm new to Scheme. I've tried debugging this piece of code and even compared it to similar solutions.</p>
  
  <pre><code>(def (myFunc x y z)
      (cond ((and (&lt;= x y) (&lt;= x z)) (+ (* y y) (* z z)))
            ((and (&lt;= y x) (&lt;= y z)) (+ (* x x) (* z z)))
            (else (+ (* x x) (* y y)))))
  </code></pre>
  
  <p>This function returns the sum of the squares of two largest numbers.</p>
  
  <p>When I run this, the interpreter gives out ";Unbound variable: y". Could you please explain the cause behind this error?</p>
  
  <p>Help is greatly appreciated :)</p>