How it works
Two engines, picked per operation
Simplify, expand and derivatives run on mathjs. Factoring and integrals run on nerdamer, a computer algebra system. Simplify asks both and keeps the shorter answer, which is how sin(x)^2 + cos(x)^2 comes back as 1.
Both libraries load in your browser the first time you open the page, about a megabyte of script, and every answer is worked out on your device as you type.
Solving equations
Write an equation with one =, or an expression on its own, which is solved as equal to zero. The equation is moved to one side, left minus right, and turned into a polynomial.
Polynomials up to cubics are solved by mathjs’s polynomialRoot, to ten significant figures, complex roots included. Anything else, such as a quartic or e^x = 2, goes to nerdamer’s solver, which gives exact roots where it can find them.
a = b → (a) − (b) = 0
Derivatives and integrals
The derivative is taken symbolically with respect to the variable you name, x by default, using the sum, product, quotient and chain rules.
An integral is an antiderivative plus a constant C. When nerdamer finds no closed form, as for e^(−x²), the calculator says so rather than guessing.
∫ f(x) dx = F(x) + C
