diff --git a/js-assembler/runtime-src/js-numbers.js b/js-assembler/runtime-src/js-numbers.js
index a0ceac9..0192b47 100644
--- a/js-assembler/runtime-src/js-numbers.js
+++ b/js-assembler/runtime-src/js-numbers.js
@@ -616,6 +616,7 @@ if (typeof(exports) !== 'undefined') {
 
     // tan: scheme-number -> scheme-number
     var tan = function(n) {
+	if (eqv(n, 0)) { return 0; }
 	if (typeof(n) === 'number') {
 	    return FloatPoint.makeInstance(Math.tan(n));
 	}
@@ -624,6 +625,7 @@ if (typeof(exports) !== 'undefined') {
 
     // atan: scheme-number -> scheme-number
     var atan = function(n) {
+	if (eqv(n, 0)) { return 0; }
 	if (typeof(n) === 'number') {
 	    return FloatPoint.makeInstance(Math.atan(n));
 	}
@@ -659,6 +661,7 @@ if (typeof(exports) !== 'undefined') {
 
     // asin: scheme-number -> scheme-number
     var asin = function(n) {
+        if (eqv(n, 0)) { return 0; }
 	if (typeof(n) === 'number') {
 	    return FloatPoint.makeInstance(Math.asin(n));
 	}
@@ -806,7 +809,7 @@ if (typeof(exports) !== 'undefined') {
     var makeComplexPolar = function(r, theta) {
 	// special case: if theta is zero, just return
 	// the scalar.
-	if (equals(theta, 0)) {
+	if (eqv(theta, 0)) {
 	    return r;
 	}
 	return Complex.makeInstance(multiply(r, cos(theta)),
diff --git a/js-assembler/runtime-src/runtime.js b/js-assembler/runtime-src/runtime.js
index 6167721..9c03af7 100644
--- a/js-assembler/runtime-src/runtime.js
+++ b/js-assembler/runtime-src/runtime.js
@@ -1535,7 +1535,7 @@
                          MACHINE.env[MACHINE.env.length - 1],
                          0,
                          'exact?');
-            return jsnums.isExact(x);
+            return jsnums.isExact(MACHINE.env[MACHINE.env.length - 1]);
         });
 
 
@@ -1872,11 +1872,11 @@
         1,
         function(MACHINE) {
             testArgument(MACHINE,
-                         'integer',
+                         'string',
                          isString,
                          MACHINE.env[MACHINE.env.length-1],
                          0,
-                         'number->string');
+                         'string->number');
             return jsnums.fromString(MACHINE.env[MACHINE.env.length-1].toString());
         });
 
diff --git a/lang/kernel.rkt b/lang/kernel.rkt
index 47654b9..0216d63 100644
--- a/lang/kernel.rkt
+++ b/lang/kernel.rkt
@@ -1,5 +1,6 @@
 #lang racket/base
-(require (prefix-in math: (only-in racket/math pi sinh))
+(require (prefix-in racket: (only-in racket/math pi sinh cosh sqr
+                                     sgn conjugate))
          (prefix-in racket: racket/base)
 	 racket/local
 	 (for-syntax racket/base))
@@ -9,7 +10,7 @@
 ;; constants
 (define constant:true #t)
 (define constant:false #f)
-(define constant:pi math:pi)
+(define constant:pi racket:pi)
 (define constant:e (racket:exp 1))
 
 
@@ -198,42 +199,46 @@
 ;;  exn:fail:contract:arity?
 ;;  exn:fail:contract:variable?
 ;;  exn:fail:contract:divide-by-zero?
-;;  abs
-;;  quotient
-;;  remainder
-;;  modulo
+  abs
+  quotient
+  remainder
+  modulo
 ;;  max
 ;;  min
-;;  gcd
-;;  lcm
-;;  floor
-;;  ceiling
-;;  round
-;;  truncate
-;;  numerator
-;;  denominator
-;;  expt
-;;  exp
-;;  log
-;;  sin
-;;  cos
-;;  tan
-;;  asin
-;;  acos
-;;  atan
-
-;;  sqrt
-;;  integer-sqrt
-;;  make-rectangular
-;;  make-polar
-;;  real-part
-;;  imag-part
-;;  angle
-;;  magnitude
-;;  inexact->exact
+  gcd
+  lcm
+  floor
+  ceiling
+  round
+  truncate
+  numerator
+  denominator
+  expt
+  exp
+  log
+  sin
+  sinh
+  cos
+  cosh
+  tan
+  asin
+  acos
+  atan
+  sqr
+  sqrt
+  integer-sqrt
+  sgn
+  make-rectangular
+  make-polar
+  real-part
+  imag-part
+  angle
+  magnitude
+  conjugate
+  ;;  inexact->exact
 ;;  exact->inexact
-;;  number->string
-;;  string->number
+  number->string
+  string->number
 ;;  procedure?
   pair?
 ;;  (undefined? -undefined?)
@@ -253,7 +258,7 @@
 ;;  real?
 ;;  rational?
 ;;  integer?
-;;  exact?
+  exact?
 ;;  inexact?
 ;;  odd?
 ;;  even?
diff --git a/tests/test-browser-evaluate.rkt b/tests/test-browser-evaluate.rkt
index d687ad3..277b418 100644
--- a/tests/test-browser-evaluate.rkt
+++ b/tests/test-browser-evaluate.rkt
@@ -610,6 +610,20 @@ EOF
 (test '(displayln (sqrt 4))
       "2\n")
 
+(test '(displayln (integer-sqrt 4))
+      "2\n")
+
+(test '(displayln (sgn 3))
+      "1\n")
+
+
+(test '(displayln (number->string 42))
+      "42\n")
+
+(test '(displayln (string->number  "42"))
+      "42\n")
+
+
 
 
 ;; Knuth's Man-or-boy-test.