all students take calculus

A mnemonic that indicates the sign values of the three common trigonometric functions (sine, tangent, and cosine) in each quadrant of a plane. (They are "all" positive in the first quadrant.) Hey, just remember that "all students take calculus." It'll help you on your trig test. A: "Is sine positive in the first quadrant?" B: "Remember 'all students take calculus'?" A: "Oh, yeah. Sine is positive in the first quadrant then! Callie, that thing you taught me, "all students take calculus," was truly a lifesaver for my trig exam!