"Kalkulačka" "Chyba" "0" "1" "2" "3" "4" "5" "6" "7" "8" "9" "SMAZAT" "VYMAZAT" "sin" "cos" "tan" "e" "ln" "log" "(" ")" "Základní funkce" "Pokročilé funkce" "Vymazat historii"