Hi, Does anyone understand how N’(x) is being calculated in Page 90 of schweser FRM notes Level 1? It says N’(x) = 1/(sqrt(2) pi * e^[(-x^2)/2] I am wondering if it really means 1/ (sqrt 2* pi) * e^[(-x^2)/2] And I can’t get the 2.89 on page 91 using BOTH formulas. Is that a typo somewhere in the notes? Thanks !