Topic Details (Notes format)

How to Calculate the Lateral Surface Area of a Cone

Subject: Mathematics

Book: Maths Mastery

A cone’s lateral surface area is given by πrl, where r is the radius of the base and l is the slant height (the distance from the tip of the cone to any point on the perimeter of the base). For instance, if r=4 cm and the slant height l=9 cm, the lateral area is π × 4 × 9 = 36π cm². This formula is especially important in designing conical shapes like funnels, ice cream cones, or architectural features (spires). Understanding the distinction between slant height and perpendicular height is crucial for correct applications of the lateral surface area formula.

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