How can I prove that Tor(R/I,R/J) $\text{Tor}_1(R/I,R/J) = (I|J)/IJ, where | denotes intersectionI \cap J)/IJ$, R where $R$ 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.

