Not sure what you want, but VBA has a built in SIN function - it takes
radians as an argument:

From help:
Sin Function


Returns a Double specifying the sine of an angle.

Syntax

Sin(number)

The required number argument is a Double or any valid numeric expression
that expresses an angle in radians.

Remarks

The Sin function takes an angle and returns the ratio of two sides of a
right triangle. The ratio is the length of the side opposite the angle
divided by the length of the hypotenuse.

The result lies in the range -1 to 1.

To convert degrees to radians, multiply degrees by pi/180. To convert
radians to degrees, multiply radians by 180/pi.



--
Regards,
Tom Ogilvy

"Mark" wrote in message
...
Anyone knows how to write in VBA following function: sin^2
(0,5) 1/2
Regards
Mark