PHP code inside Javascript function not working(insert into) [duplicate]

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PHP insert into query not sending anything to database, maybe because it's inside Javascript function, i don't know yet.. Anyone could help please? thanks.

<script>
function getMeta(){   
    var img = new Image();
    img.onload = function(){
        if (this.width != 468 && this.height != 60)
                  {alert( 'Error : only these image sizes are accepted : 468x60' );
                  return false;}
                  
                  else
                  alert( 'loaded successfully' );
                  document.getElementById('form1').submit();
                  <?php

  include("connection.php");
    $email=$_POST["t1"];
    $email=addslashes($email);
        $img=$_POST["t2"];
        $img=addslashes($img);
        $target=$_POST["t3"];
        $target=addslashes($target);
  
$sql=mysql_query("insert into b1(email, img, target) values ('$email', '$img', '$target')");
   
?>
    };
        img.onerror = function() {alert( 'Error : this is not a valid image');
        return false;
         };
    img.src = document.getElementById('t2').value;
        return true;
}


</script>