I want to write a proof for two similar propositions, both proofs are similar except that all the $\cap$s in the first proof are replaced with $\cup$s respectively. How can I write formally and clearly, I mean, like a native-speaker, and avoid the repetition?
I write the following sentence in the last part of my proof.
The latter one is similar to the previous one, except replacing $\cap$s with $\cup$s.
Is this a readable proof for you? Or how can I modify this?