Hexagonal Pyramid
1. **Problem statement:** We have a regular hexagonal pyramid with a lateral edge of length 6 cm and a base side length of 3 cm. We need to find its volume in cubic centimeters.
2. **Relevant formulas:**
- The volume $V$ of a pyramid is given by $$V = \frac{1}{3} \times \text{Base Area} \times \text{Height}$$
- The base is a regular hexagon, so its area $A$ can be calculated by $$A = \frac{3\sqrt{3}}{2} s^2$$ where $s$ is the side length of the hexagon.
3. **Calculate the base area:**
Given $s = 3$ cm,
$$A = \frac{3\sqrt{3}}{2} \times 3^2 = \frac{3\sqrt{3}}{2} \times 9 = \frac{27\sqrt{3}}{2} \text{ cm}^2$$
4. **Find the height of the pyramid:**
- The lateral edge is the slant edge from the apex to a vertex of the base, length 6 cm.
- The height $h$ is the perpendicular distance from the apex to the base plane.
- The distance from the center of the hexagon to a vertex (circumradius $R$) is $$R = s = 3 \text{ cm}$$ for a regular hexagon.
- The lateral edge, height, and circumradius form a right triangle with the lateral edge as hypotenuse:
$$6^2 = h^2 + 3^2$$
$$36 = h^2 + 9$$
$$h^2 = 27$$
$$h = \sqrt{27} = 3\sqrt{3} \text{ cm}$$
5. **Calculate the volume:**
$$V = \frac{1}{3} \times \frac{27\sqrt{3}}{2} \times 3\sqrt{3} = \frac{1}{3} \times \frac{27\sqrt{3}}{2} \times 3\sqrt{3}$$
Simplify inside:
$$3\sqrt{3} \times \sqrt{3} = 3 \times 3 = 9$$
So,
$$V = \frac{1}{3} \times \frac{27}{2} \times 9 = \frac{1}{3} \times \frac{243}{2} = \frac{243}{6} = 40.5 \text{ cm}^3$$
**Final answer:** The volume of the pyramid is $40.5$ cubic centimeters.