For example, one real analysis student was able to prove that 0.333... = ​1⁄3 using a supremum definition, but then insisted that 0.999... < 1 based on her earlier understanding of long division.
Sebagai contoh, seorang siswa analisis real mampu membuktikan 0,333… = 1⁄3 menggunakan definisi supremum, namun tetap bersikeras bahwa 0,999… < 1 didasari oleh pemahaman pembagian panjangnya.