2day math lesson is quite hard n confusing

2day my math teacher juz go thuru e last part topics in matrices which is adjoint is half determinant n matrices join together n last one is inverse A is combination of determinant n tday lesson. Nxt week onwards is revision n last assginment 4 math. I also want 2 prepare 4 exam nxt week onwards. My aiming grade A or B or matain my GPA. Tmr go again after that math no more new chapter finish already.