WAEC - Mathematics (2001 - No. 44)
A solid cylinder of radius 7cm is 10 cm long. Find its total surface area.
\(70\pi cm^2\)
\(189\pi cm^2\)
\(210\pi cm^2\)
\(238\pi cm^2\)
解释
S = \(2\pi r^2 + 2\pi rh\)
= \(2\pi r(r + h)\)
= \(2\pi (7) (7 + 10)\)
= \(238\pi cm^2\)