28.3.4 Surface Area of Cylinders, Cones, and Truncated Cones
28.3 Unfolding Surfaces and Surface Area
Point 4 of 5
28.3.4 Surface Area of Cylinders, Cones, and Truncated Cones
Core idea
The lateral-area formulas come straight from the net: 2πrl for a cylinder, πrl for a cone, and the larger circle minus the smaller one for a truncated cone.
Module goal. Use nets to flatten a solid's surface into a plane figure, turning surface-area problems into the flat-area calculations you already know.
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