diff --git a/src/pkg/math/tanh.go b/src/pkg/math/tanh.go
index 7305be66c7..cf0ffa1923 100644
--- a/src/pkg/math/tanh.go
+++ b/src/pkg/math/tanh.go
@@ -65,7 +65,7 @@ var tanhQ = [...]float64{
 	4.84406305325125486048E3,
 }
 
-// Tanh computes the hyperbolic tangent of x.
+// Tanh returns the hyperbolic tangent of x.
 //
 // Special cases are:
 //	Tanh(±0) = ±0