Merge pull request #29016 from SSaishruthi:cosh_doc

PiperOrigin-RevId: 251881337

tensorflow/core/api_def/base_api/api_def_Acosh.pbtxt

@@ -1,4 +1,13 @@
 op {
   graph_op_name: "Acosh"
   summary: "Computes inverse hyperbolic cosine of x element-wise."
+  description: <<END
+Given an input tensor, the function computes inverse hyperbolic cosine of every element.
+Input range is `[1, inf]`. It returns `nan` if the input lies outside the range.
+
+```python
+x = tf.constant([-2, -0.5, 1, 1.2, 200, 10000, float("inf")])
+tf.math.acosh(x) ==> [nan nan 0. 0.62236255 5.9914584 9.903487 inf]
+```
+END
 }