Question about a circuit problem with opamp
Call the node connected to the negative terminal of the voltage source ground.

The left side of R1 is at 0 V because it's connected to ground. 

The right side of R1 is at 0 V because it's connected to the virtual ground at the summing node of the op-amp. 

Therefore there's no voltage across the resistor, so no current through it. 


  If i2 is not equal to 0, where does the current go after the first resistor?


Into the output pin of the op-amp.

The output pin of the op-amp behaves (somewhat) like an ideal voltage source. An ideal voltage source can have whatever current is necessary through it, positive or negative, to produce the voltage it is sourcing.