下列运算中,正确的是( )
a 2 • a 5 = a 10
( a ﹣ b ) 2 = a 2 ﹣ b 2
(﹣ 3 a 3 ) 2 = 6 a 6
﹣ 3 a 2 b + 2 a 2 b =﹣ a 2 b
试题篮