"It is in perilous times like these that the office of auditor general assumes even greater responsibility than ever before," Wagner said.
Treasurer Rob McCord, a Democrat from Montgomery County, choked up as he told a packed hearing room that he and his staff would "work in a way that will make our moms proud."
He replaced Robin Wiessmann, who was appointed to finish Bob Casey's term after Casey was elected to the U.S. Senate.
Corbett, an Allegheny County Republican, defeated his closest challenger, John Morganelli, the Democratic Northampton County district attorney, by nearly 7 percentage points in November.
Wagner's margin over Republican Chet Beiler was more than 21 points. McCord ran more than 12 points ahead of Republican Tom Ellis.
The state constitution sets Tuesday as the start of the four-year terms for the three offices.
The row offices have often been a stepping stone to higher office in Pennsylvania, and both Corbett and Wagner have been mentioned as possible gubernatorial candidates in 2010.