Question Number 167722 by SAMIRA last updated on 23/Mar/22
$$\frac{\mathrm{2}}{\boldsymbol{\mathrm{Z}}}\:=\:\frac{\mathrm{1}}{\boldsymbol{\mathrm{a}}}+\frac{\mathrm{1}}{\boldsymbol{\mathrm{b}}} \\ $$$$\boldsymbol{\mathrm{Z}}\:=\:???\:{help} \\ $$
Commented by MJS_new last updated on 23/Mar/22
$$\mathrm{law}\:\mathrm{of}\:\mathrm{adding}\:\mathrm{fractions} \\ $$$$\frac{{o}}{{p}}+\frac{{q}}{{r}}=\frac{{o}×{r}}{{p}×{r}}+\frac{{p}×{q}}{{p}×{r}}=\frac{{o}×{r}+{p}×{q}}{{p}×{r}} \\ $$$$\frac{\mathrm{2}}{{Z}}=\frac{\mathrm{1}}{{a}}+\frac{\mathrm{1}}{{b}} \\ $$$$\frac{\mathrm{2}}{{Z}}=\frac{{a}+{b}}{{a}×{b}} \\ $$$$\frac{{Z}}{\mathrm{2}}=\frac{{a}×{b}}{{a}+{b}} \\ $$$${Z}=\frac{\mathrm{2}×{a}×{b}}{{a}+{b}} \\ $$
Answered by pnuvu last updated on 23/Mar/22
$$\boldsymbol{{Z}}=\frac{\mathrm{2}{ab}}{{a}+{b}} \\ $$