How can I prove that Tor(R/I,R/J) = (I|J)/IJ$\text{Tor}_1(R/I,R/J) = (I \cap J)/IJ$, where | denotes intersection, R$R$ is a ring and I, J$I, J$ ideals.
Moreover, if we suppose R=I+J$R=I+J$, how do I prove that Tor (R/I,R/J)=0$\text{Tor}_1(R/I,R/J)=0$?
Ps: No, this is not a homework question.