div class=trans-pagebutton class=gotoPage data-page=1Page 1button div class=trans-imageimg data-url=documentsinger-and-thorpe-lecture-notes-on-elementary-topology-ruffinocursos2018-2htmlpage=1 data-page=1 class=trans-thumb lazyload alt=Page 1: Singer and Thorpe - Lecture notes on elementary topology ruffinocursos2018-2 · 6 SOME polNT SET TOPOLOGY Definition A topological space is a set S together with a collection loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mM8Uw8AAh0BTZud3BwAAAAASUVORK5CYII= data-src=https:reader036fdocumentsnetreader036viewer20220816075ed12266c91078260375501ahtml5thumbnails1jpg width=140 height=200 divdivdiv class=trans-pagebutton class=gotoPage data-page=2Page 2button div class=trans-imageimg data-url=documentsinger-and-thorpe-lecture-notes-on-elementary-topology-ruffinocursos2018-2htmlpage=2 data-page=2 class=trans-thumb lazyload alt=Page 2: Singer and Thorpe - Lecture notes on elementary topology ruffinocursos2018-2 · 6 SOME polNT SET TOPOLOGY Definition A topological space is a set S together with a collection loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mM8Uw8AAh0BTZud3BwAAAAASUVORK5CYII= data-src=https:reader036fdocumentsnetreader036viewer20220816075ed12266c91078260375501ahtml5thumbnails2jpg width=140 height=200 divdivdiv class=trans-pagebutton class=gotoPage data-page=3Page 3button div class=trans-imageimg data-url=documentsinger-and-thorpe-lecture-notes-on-elementary-topology-ruffinocursos2018-2htmlpage=3 data-page=3 class=trans-thumb lazyload alt=Page 3: Singer and Thorpe - Lecture notes on elementary topology ruffinocursos2018-2 · 6 SOME polNT SET TOPOLOGY Definition A topological space is a set S together with a collection loading=lazy src=data:imagegifbase64iVBORw0KGgoAAAANSUhEUgAAAAEAAAABCAQAAAC1HAwCAAAAC0lEQVR42mM8Uw8AAh0BTZud3BwAAAAASUVORK5CYII=...