--- loncom/homework/default_homework.lcpm	2001/02/19 20:31:53	1.17
+++ loncom/homework/default_homework.lcpm	2001/02/20 23:46:25	1.18
@@ -140,8 +140,10 @@ sub random {
 }
 
 sub tan  { sin($_[0]) / cos($_[0]) }
+sub atan { atan2($_[0], 1); }
 sub acos { atan2(sqrt(1 - $_[0] * $_[0]), $_[0] ); }
 sub asin { atan2($_[0], sqrt(1- $_[0] * $_[0]) );  }
+sub log10 { log($_[0])/log(10); }
 
 sub html {
   if ( $external::target eq "web" ) {