Pre Calculus is a bridge between Algebra and Calculus. It is a continuation of Algebra 2. Topics of pre calculus like Sequences & Series, Trigonometry, Polar Coordinates, Logarithmic and Exponential Functions are all pre requisites for studying AP Calculus or Engineering in the future.
Pre calculus concepts teach a student to THINK logically. This area of math is not different from algebra, trigonometry, coordinate geometry or calculus; in fact, it combines elements of all these three areas of study.
High School students usually study precalculus in the 10th or 11th grade. A student typically starts studying pre calculus after having learned trigonometry, linear inequalities and some basic functions.Many US states require that high school students study pre calculus in order to graduate high school. Pre Calculus is also routinely used on many state standardized tests to measure student achievement. The SAT and ACT college entrance exams also involve many problems from pre calculus.

