Try doing some basic maths questions in the Lean Theorem Prover. Functions, real numbers, equivalence relations and groups. Click on README.md and then on "Open in CoCalc with one click".
1[package] 2name = "maths-challenges" 3version = "0.1" 4lean_version = "3.4.2" 5path = "src" 6 7[dependencies] 8mathlib = {git = "https://github.com/leanprover-community/mathlib", rev = "dd8da5165bd00b07408dbb87173e96908c6926a4"} 9 10