PROBLEM WITH PI π

[yagomestre64]

Hi, i've bought a HP prime calculator and im having some problems with it, when i make sen(π) in CAS mode, it works correctly and gives me 0 as an answer, but when i compute it out of CAS mode, it returns to me -2E-13, a pretty small number, close to 0 but no 0, the problem is that , out of CAS mode, the calculator makes an approximation of π to the 11th decimal digit, so the value of the sin(π) is not exactly 0, how couls i fix this? thanks in advance