Question Number 150136 by Tawa11 last updated on 09/Aug/21
Commented by Tawa11 last updated on 09/Aug/21
$$\mathrm{Thanks}\:\mathrm{sir}.\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you}.\:\mathrm{I}\:\mathrm{appreciate}\:… \\ $$
Answered by mr W last updated on 09/Aug/21
$${R}=\frac{\mathrm{5}}{\mathrm{2}} \\ $$$$\frac{{R}−{r}}{{R}+{r}}=\frac{\mathrm{1}}{\:\sqrt{\mathrm{5}}} \\ $$$${r}=\frac{\sqrt{\mathrm{5}}−\mathrm{1}}{\:\sqrt{\mathrm{5}}+\mathrm{1}}{R}=\frac{\left(\mathrm{3}−\sqrt{\mathrm{5}}\right){R}}{\mathrm{2}}=\frac{\left(\mathrm{3}−\sqrt{\mathrm{5}}\right)\mathrm{5}}{\mathrm{4}}\approx\mathrm{0}.\mathrm{955} \\ $$
Commented by Tawa11 last updated on 09/Aug/21
$$\mathrm{Thanks}\:\mathrm{sir}.\:\mathrm{God}\:\mathrm{bless}\:\mathrm{you}.\:\mathrm{I}\:\mathrm{appreciate}. \\ $$