PostgreSQL/Math Functions/asin

asin(x): Returns the inverse sine of x

postgres=# -- asin(x): Returns the inverse sine of x
postgres=# SELECT asin(1), asin(0), asin(-1),  asin(sin(1)) AS inverse_example;
      asin       | asin |       asin       | inverse_example
-----------------+------+------------------+-----------------
 1.5707963267949 |    0 | -1.5707963267949 |               1
(1 row)
postgres=#