this is, without exaggeration, THE BEST mathematical textbook i've laid eyes on. the exposition is perfectly lucid, every concept is thoroughly explained and motivated, the proofs are short and elegant, plenty of exercises, thoroughly covers every topic an undergraduate needs to know, with the small exception of multilinear algebra (there is a short chapter on it, but it's reminiscent of how analysts develop the subject for manifolds); also quotient spaces are completely relegated to the appendix for some reason, but that doesn't affect the text in the slightest
this should be REQUIRED reading for EVERY maths/physics undergraduate, you literally shouldn't be allowed to graduate without first reading this once
this book has honestly spoiled me, nothing else comes close to this...