title: If statement 3 conditions Bash
body: <p>I want to do an if statement with three conditions that have to be satisfied at the same time. I am using Ubuntu Bash for Windows and the values $c1, $c2 and $c3 are non-integer (decimal negative numbers).</p>
  
  <pre><code>if [ (( $(echo "$c1 &lt; 0" | bc -l) )) ]  &amp;&amp; [ (( $(echo "$c2 &lt; 0" | bc -l) )) ] &amp;&amp; [ (( $(echo "$c3 &lt; 0" | bc -l) )) ];
      then
        &gt;&amp;2 echo -e "   ++ Constraints OK"
  
  else
        &gt;&amp;2 echo -e "   ++ Constraints WRONG"
  
  fi
  </code></pre>
  
  <p>However, I get the following syntax error in the if line: <code>syntax error near unexpected token `('</code></p>
  
  <p>If I just put one condition:</p>
  
  <pre><code>if (( $(echo "$c1 &lt; 0" | bc -l) )); 
  </code></pre>
  
  <p>it works, but when I add the three of them as AND (<code>&amp;&amp;</code>), I get the error. Can anyone help me?</p>