8 The first five terms of a sequence are shown.
4, 12, 36, 108, 324, ...
Write an explicit function to model the value of the nth term in the sequence such that
f(1) = 4.
to
f(n) =

Find the volume v of the solid obtained by rotating the region bounded by the given curves about the specified line. y = x â’ 1 , y = 0, x = 5; about the x-axis v = sketch the region. sketch the solid, and a typical disk or washer.