Obliczam promień podstawy (z twierdzenia cosinusów) [latex](2r)^2=l^2+l^2-2l cdot l cosalpha[/latex] [latex]4r^2=6^2+6^2-2 cdot 6^2 cdot frac{1}{9}[/latex] [latex]4r^2=36+36-2 cdot 36cdot frac{1}{9}[/latex] [latex]4r^2=72-8[/latex] [latex]4r^2=64 /:4[/latex] [latex]r^2=16[/latex] [latex]r= sqrt{16}[/latex] [latex]r=4cm[/latex] Obliczam [latex]h[/latex] [latex]h^2=l^2-r^2[/latex] [latex]h^2=6^2-4^2[/latex] [latex]h^2=36-16[/latex] [latex]h^2=20[/latex] [latex]h= sqrt{20}[/latex] [latex]h=2 sqrt{5}cm[/latex] Obliczam V walca [latex]V=pi r^2h[/latex] [latex]V=4^2 cdot 2 sqrt{5}pi[/latex] [latex]V=16 cdot 2 sqrt{5}pi[/latex] [latex]V=32 sqrt{5}pi cm^3[/latex]
