I just started using python, and am having difficulty with a very basic program. I want to calculate the cosine of -20 degrees. It is my understanding that the default value is
Per the Python documentation:
math.degrees(x)
Convert angle x from radians to degrees.
That means you are attempting to convert -20 radians to degrees which isn't desired.
Also per the documentation:
math.cos(x)
Return the cosine of
x
radians.
This means math.cos
finds the cosine of the passed argument in radians, not degrees. That means your code currently changes -20 radians to degrees, then finds the cosine of that as if it were radians... you can see why that's a problem.
You need to convert -20 degrees to radians, and then find the cosine. Use math.radians:
math.cos(math.radians(-20))
You need to input in radians, so do
math.cos(math.radians(-20))
math.radians(-20) converts -20 degrees to radians.
math.degrees
takes a number of radians and produces a number of degrees. You need the opposite conversion - you have a number of degrees, and you need to produce a number of radians you can pass to math.cos
. You need math.radians
:
math.cos(math.radians(-20))