I was a math major in college and I have used almost none of the math-skills I learned in college while in API(and looking ahead to Primary, probably will not use them there either). Knowing calculus and how to write out a Delta-Epsilon Proof is completely different than doing basic arithmetic in your head. In some instances my math-knowledge confused me more because they dumb down Aero so much that the equations do not match up with the graphs they give you.
If you're worried about being able to do the basic arithmetic in the cockpit, start practicing basic arithmetic and don't worry about learning how to prove that the square-root of two is an Irrational number.
If you're worried about being able to do the basic arithmetic in the cockpit, start practicing basic arithmetic and don't worry about learning how to prove that the square-root of two is an Irrational number.