(Solved): 2.38 A weighted summer circuit using an ideal op amp as shown in Fig. \( 2.10 \) has three inputs ...

2.38 A weighted summer circuit using an ideal op amp as shown in Fig. \( 2.10 \) has three inputs using \( 20-\mathrm{k} \Omega \) resistors and a feedback resistor of \( 50 \mathrm{k} \Omega \). A signal \( v_{1} \) is connected to two of the inputs while a signal \( v_{2} \) is connected to the third. Express \( v_{O} \) in terms of \( v_{1} \) and \( v_{2} \). If \( v_{1}=1 \mathrm{~V} \) and \( v_{2}=-1 \mathrm{~V} \), what is \( v_{O} \) ?