The term CALC PREREQUISITE is composed of three crossword solutions: TRIG (4 letters), ALG (3 letters), and MATH (4 letters). These terms refer to the prerequisites for taking a calculus course. Trigonometry is a branch of mathematics that studies relationships involving lengths and angles of triangles. Algebra is a branch of mathematics that uses symbols to represent numbers and quantities in equations and formulas. Math is a general term for the study of numbers, shapes, and patterns. All three of these subjects are necessary for a student to have a basic understanding of calculus.