The β¬17 βAmsterdam Travel Ticketβ covers transportation to and from Schiphol by train or using bus 397 (operated by Connexxion) and all public transportation in Amsterdam (in particular the bus, trams and metros operated by GVB). This offering from Connexxion seems similar, not sure why there is a price difference.
GVB offers a much cheaper day ticket but it would not cover NS trains or the Connexxion bus to Schiphol. It is still possible to reach Amsterdam city center from the airport using bus 69 (as this one is operated by GVB) but the connections are likely to be longer and more cumbersome.
Note that individual tickets or a train ticket + a GVB day pass for the two trips inside the city are likely to be cheaper but I am assuming you also appreciate a day pass for the convenience.