I have a midterm tomorrow and I find I'm quite slow at finding the determinant of a 3x3 matrix. Basically I'll only need to find the determinant to find the characteristic polynomial (at least for this class) and my prof on the board does it so fast, I'm wondering if there's some trick I missed out on. I feel like it takes me too much time to get the determinant of 3x3 matrices. Also my first time posting, long time lurker lol. Thanks.