Precalculus

Precalculus

Precalculus is the bridge between algebra and calculus — the toolkit you build before tackling derivatives and integrals. These solvers cover the recurring topics: counting, complex numbers, polynomial manipulation and exponential equations.

A precalculus course gathers the pieces of algebra and trigonometry that calculus assumes you already know. The topics look unrelated at first — combinations and complex numbers, the binomial theorem and polynomial division — but they all return throughout calculus, so the time spent here pays off later.

Counting: permutations and combinations

nPr counts ordered arrangements; nCr counts unordered selections. Both come from the factorial n! and underpin the binomial coefficients.

The binomial theorem

Expand (a + b)ⁿ as a sum of binomial-coefficient terms. The same coefficients appear in Pascal's triangle and in counting subsets.

Complex numbers

A complex number a + bi extends arithmetic to include the square root of −1. The calculator adds, subtracts, multiplies and divides them using the conjugate trick.

Polynomial long division and exponentials

Long division splits a polynomial into a quotient plus a remainder, mirroring integer long division. Exponential equations bring the unknown out of the exponent with a logarithm.

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Frequently asked questions

Why is precalculus needed before calculus?

Calculus assumes fluency with functions, polynomials, trigonometry and the binomial theorem — precalculus is where those become automatic.

What does nCr mean?

It is the number of ways to choose r items from n without regard to order, equal to n! divided by r! and (n − r)!.

Can the binomial tool handle negative or fractional exponents?

It handles whole-number exponents. Negative or fractional exponents give an infinite series, which is a calculus topic.