title: Trigonometry sin return negative
body: <p>I made this code in Python</p>
  
  <pre><code>def hitsin(a):
      a = a*57.3
      return math.sin(a)
  </code></pre>
  
  <p>so whenever i put hitsin(x) the x converted to radian. I confuse when I put hitsin(90) the answer is not 1 or any number near 1, but negative (it was -0.9971392129043587). Am I doing it wrong?</p>
  
  <p>p.s: I also try to write the same kind of code in C</p>
  
  <pre><code>#include &lt;stdio.h&gt;
  #include &lt;math.h&gt;
  
  int main(){
      float degree;
      float result;
  
      degree = 90;
      degree = degree*57.3;
      result  = cos(result);
  
      printf("%f",result);
  
      return 1;
  }
  </code></pre>
  
  <p>But the answer is same.</p>
  
  <p>sincerely yours
  Giri</p>