Shell method

A region $R$‍ is bounded above by the graph of $y=\cos x$‍, bounded below by the graph of $y=\sin (x^2)$‍, and bounded on the right by the $y$‍-axis.

The upper and lower curves intersect at $x=c$‍ for some constant $c<0$‍.

Rotating region $R$‍ about the vertical line $x=2$‍ generates a solid of revolution $S$‍.