Question

Find the area of the surface generated by revolving the curve x = (e^y + e^-y) / 2 from x = 0 to x = ln(2).

Answer 1

Here's the calculation of area
π [ ln 2+ 1 / 2sinh(2 ln 2) ]=π [ln 2+1 4(2^2−2^−2) ]

=π [ln 2+1 / 4( 4− 1 / 4)]=π (ln 2+15 / 16) ≈ 5.122