[latex]a = 1\r = frac{a(1+sqrt{2})}{2} - promien okregu wpisanego w osmiokat foremny\\O = 2 pi r = 2 pi cdotfrac{1(1+sqrt{2})}{2} = (sqrt{2}+1) pi [j]\\P = pi r^{2} = pi cdot[frac{1(1+sqrt{2})}{2}]^{2} = pi cdotfrac{1+2sqrt{2}+2}{4}=frac{2 sqrt{2}+3}{4} pi [j^{2}][/latex]