Speed

Speed is the absolute value of velocity: speed =  . This is the definition of speed, but hardly enough to be sure students know about speed and its relationship to velocity and acceleration. Velocity is a vector quantity; that is, it had both a direction and a magnitude. The magnitude of velocity vector is the speed.…

Open or Closed?

About this time of year you find someone, hopefully one of your students, asking, “If I’m finding where a function is increasing, is the interval open or closed?” Do you have an answer? This is a good time to teach some things about definitions and theorems. The place to start is to ask what it…