Геометриялык прогрессия

[latex]b_{11}=b_5*q^{(11-5)}; \\ 1647=61*q^6; \\ q^6=1647:61=27=3^3; \\ q=3^{ \frac{3}{6}} =3^{ \frac{1}{2}} = \sqrt{3} [/latex] [latex]b_{11}=b_9*q^{(11-9)}=b_9*q^2; \\ \\ b_9= \frac{b_{11}}{q^2} = \frac{1647}{( \sqrt{3} )^2} =\frac{1647}{3} =549 ;[/latex] [latex]b_5=b_2*q^{(5-2)}=b_2*q^3; \\ \\ b_2= \frac{b_5}{q^3}= \frac{61}{( \sqrt{3} )^3}= \frac{61}{3 \sqrt{3} } [/latex].