6
One possibility: \documentclass{article} \usepackage[utf8]{inputenc} \usepackage[T1,T2A]{fontenc} \usepackage[english,russian]{babel} \usepackage[a5paper]{geometry} \usepackage{amsthm,thmtools} \usepackage[framemethod=tikz]{mdframed} \usepackage{amsmath,amssymb} \usetikzlibrary{shadows.blur} \us...