NORMAL CARTESIAN EQUATIONS
Graphmatica's equation parser will automatically isolate the variable
y wherever it is in the equation. It will graph some relations, like circles (
x^2 + y^2 = 36) and ellipses (
x^2/3 + y^2/4 = 20), as well as hyperbolas, sideways parabolas (
x = y^2) and many other conic sections. (Consult a good Algebra II textbook for help on their formulas.) The only limitation for functions is that there must be a single occurrence of one of the variables
x. Graphmatica cannot perform the factoring needed to isolate the variable
y when it occurs more than once (e.g.
x+cos x = y^2+3y). The relation graphing module (for graphs which may have more than one y-value for a given x value) works like this: if in isolating the
y in an equation Graphmatica finds an even power of it (i.e.
y^2), it makes two equations for that graph, one with the positive and one with the negative root. This method by no means covers all possible relations, but it is adequate for the most common.