Some return values for MathF.Pow() are wrong (#9571)

Author: Psychpsyo

xml/System/MathF.xml

@@ -1657,8 +1657,9 @@ The value of this field is 3.14159274.
   
 |Parameters|Return value|  
 |----------------|------------------|  
-|`x` or `y` = `NaN`.|`NaN`|  
-|`x` = Any value except `NaN`; `y` = 0.|1|  
+|`x` is any value; `y` = 0.|1|  
+|`x` = 1; `y` is any value.|1|  
+|`x` or `y` = `NaN` (except if `y` = 0 or `x` = 1).|`NaN`|  
 |`x` = `NegativeInfinity`; `y` < 0.|0|  
 |`x` = `NegativeInfinity`; `y` is a positive odd integer.|`NegativeInfinity`|  
 |`x` = `NegativeInfinity`; `y` is positive but not an odd integer.|`PositiveInfinity`|  
@@ -1670,7 +1671,6 @@ The value of this field is 3.14159274.
 |`x` < -1 or `x` > 1; `y` = `PositiveInfinity`.|`PositiveInfinity`|  
 |`x` = 0; `y` < 0.|`PositiveInfinity`|  
 |`x` = 0; `y` > 0.|0|  
-|`x` = 1; `y` is any value except `NaN`.|1|  
 |`x` = `PositiveInfinity`; `y` < 0.|0|  
 |`x` = `PositiveInfinity`; `y` > 0.|`PositiveInfinity`|