Add:
1 + 2 = add(1, 2)					(should be 3)
-3 + 4 + 5 + -6 = add(-3, 4, 5, -6)			(should be 0)
3.2 + 1.47 + 6.3999 = add(3.2, 1.47, 6.3999)		(should be 11.0699)

Subtract:
1 - 2 = sub(1, 2)				(should be -1)
10 - -4 = sub (10, -4)				(should be 14)
3.4 - 0.02 = sub	(3.4, 0.02)			(should be 3.38)

Multiply:
2 * 4 = mul(2, 4)				(should be 8)
-4 * 6 * 3 = mul(-4, 6, 3)			(should be -72)
1.5 * 3.2 = mul(1.5, 3.2)				(should be 4.8)

Divide:
8 / 4 = div(8, 4)				(should be 2)
-6 / 2 = div(-6, 2)				(should be -3)
4.5 / 1.8 = div(4.5, 1.8)				(should be 2.5)

Maths library:
absoulte value -3.2 = abs(-3.2)		(should be 3.2)
arctangent of 2.3 / 1.7 = atan2(2.3, 1.7)	(should be approx 0.934)
cosine of 1.047 = cos(1.047)	(should be approx 0.5)
sine of 0.523 = sin(0.523)	(should be approx 0.5)
exponential of 1.45 = exp(1.45)	(should be approx 4.263)
integer portion of 2.532 = int(2.532)		(should be 2)
logarithm of 2.718 = log(2.718)	(should be approx 1.0)
square root of 36 = sqrt(36)			(should be 6)
random number in range 0 to 10000 = rand(10000)
random number in range 0 to 1 = rand()
seed random number generator with 2 srand(2)
generate 3 random numbers: rand(), rand(), rand()
seed random number generator with 2 srand(2)
generate 3 random numbers: rand(), rand(), rand()

Advanced use:
#define TEN 10
#define FOUR 4
TEN + FOUR = add(TEN, FOUR)				(should be 14)
(10 + 2) * 4 = mul( add(10, 2), 4)		(should be 48)
cosine 60 * (pi/180) = cos( mul(60, div(M_PI, 180)) )	(should be 0.5)
