BBC27 天
How to show a cone's surface area = π × r × slant length
Image caption, ...you've done it! The sectors rearranged into the rectangle show the area of the curved surface of the cone = π × radius × slant length.
BBC6 年
How to prove a cone's surface area = π × r × slant length
Image caption, ...you've done it! The sectors rearranged into the rectangle show the area of the curved surface of the cone = π × radius × slant length.