Initial value:
x₀ =

Instructions: The iteration formula should be a function of the variable x. The program knows how to parse only rational functions of x. Use + for addition, - for subtraction, / for division, * for multiplication, and x^N for powers of x. Implied multiplication by a numeric coefficient should work (i. e. 5x for 5*x), and parentheses are necessary to get the order of operations right. For example, use (x^2 - 2)/(2x), rather than (x^2-2)/2x.