**fabs()** – Gets the absolute value of the value in parentheses. Works like ABS() function in Visual Basic. fabs(-123) = 123, fabs(34) = 34.
**ceil()** – Find the ceiling integer. Kind of like rounding up. Same as INT(x+1) in Visual Basic. ceil(3.1) = 4.
**floor()** – Find the floor integer. Kind of like rounding down. Same as INT(x) in Visual Basic. floor(3.6) = 3.
**exp()** – Find the exponential value.
**pow()** – Raise a number to the power. pow(3,6) = 3^6 in Visual Basic.
**rand()** – Generate a pseudo random number. Function is RND(x) in Visual Basic. A good discussion on random numbers in Objective C can be found here.
**srandom()** – Generate a seed for the random number generator. This is done with the Randomize statement in Visual Basic.
**sqrt()** – Find out the square root of a number. sqrt(x) = x^(1/2) in Visual Basic.