You can experiment with different solids by entering your own expressions for f(x) and g(x) in the provided input fields. The parameters a, b are the end-points of the interval. When you enter your own expressions for [math]f(x)[/math] and [math]g(x)[/math], make sure that [math]g(x)\le f(x)[/math] for all [math]x\in\left[a,b\right][/math].[br][br]You can restore the original state of the illustration by clicking the two half-arrows in the upper right corner of the user interface part of the illustration.