i don't understand how i am supposed to use that code

this is what i got:

a is the angle in degrees
s is the initian speed of the object
dh is really dh/dt, the rate of change of the height of the object with respect to time

a=45
dh=sin(a)*s

i need that dh (dh/dt) value for a formula,
my problem is it calculates sin(45) as .850935 when sin(45) in degrees is .7071