bpo-37548: Document range of atan, acos and asin (GH-14717)
diff --git a/Doc/library/math.rst b/Doc/library/math.rst
index bfce41a..be953cf 100644
--- a/Doc/library/math.rst
+++ b/Doc/library/math.rst
@@ -366,17 +366,20 @@
.. function:: acos(x)
- Return the arc cosine of *x*, in radians.
+ Return the arc cosine of *x*, in radians. The result is between ``0`` and
+ ``pi``.
.. function:: asin(x)
- Return the arc sine of *x*, in radians.
+ Return the arc sine of *x*, in radians. The result is between ``-pi/2`` and
+ ``pi/2``.
.. function:: atan(x)
- Return the arc tangent of *x*, in radians.
+ Return the arc tangent of *x*, in radians. The result is between ``-pi/2`` and
+ ``pi/2``.
.. function:: atan2(y, x)