translate English to French: Show that there are in nitely many digitally divisible integers. PROBLEM 4 An acute-angled triangle has unit area.
PROBLEME 5 Etant donn 7 nombres r els, d montrer qu'il en est deux parmi eux, not s et , e e e e tels que, 1 , 0 1+  p 3 x y x y xy :