Determine the closed loop transfer function C(s) / R(s) for the block diagram shown in Fig.
1
\(\frac{{C\left( s \right)}}{{R\left( s \right)}} = \frac{{{G_1}}}{{1 - {G_1}{H_1} - {G_1}{H_1}{H_2}}}\)
2
\(\frac{{C\left( s \right)}}{{R\left( s \right)}} = \frac{{{G_1}}}{{1 + {G_1}{H_1} + {G_1}{H_2}}}\)
3
\(\frac{{C\left( s \right)}}{{R\left( s \right)}} = \frac{{{G_1}}}{{1 - {G_1}{H_1} + {G_1}{H_2}}}\)
4
\(\frac{{C\left( s \right)}}{{R\left( s \right)}} = \frac{{{G_1}}}{{1 + {G_1}{H_1} + {G_1}{H_1}{H_2}}}\)
5
None of these