The discussion centers on the equations of projectile motion when acceleration is not constant. Participants emphasize the need for calculus to derive these equations, starting from Newton's second law (F=ma). They suggest that the standard kinematic equations do not apply directly in cases of variable acceleration, requiring integration of forces to find velocity and position over time. A specific equation for non-constant acceleration is mentioned, involving double integration of acceleration. Understanding these concepts necessitates a solid grasp of calculus principles.