1:$V_{0}=\frac {R_{1}+R_{2}}{R_{1}}\left( V_{2}-V_{1}\right) $
2:$V_{0}=\frac {R_{1}+R_{2}}{R_{2}}\left( V_{2}-V_{1}\right) $
3:$V_{0}=\frac {R_{1}+R_{2}}{R_{2}-R_{1}}\left( V_{2}-V_{1}\right) $
4:$V_{0}=\frac {R_{1}}{R_{2}}\left( V_{2}-V_{1}\right) $
5:$V_{0}=\frac {R_{2}}{R_{1}}\left( V_{2}-V_{1}\right) $