а) (4(3a+1)-3a)((4(3a+1)+3a)=(12a+4-3a)(12a+4+3a)=(9a+4)(15a+4)
б) (8x-3(2x-2))(8x+3(2x-2))=(8x-6x+6)(8x+6x-6)=(2x+6)(14x-6)
в) (2(2p-3)-5p)(2(2p-3)+5p)=(4p-6-5p)(4p-6+5p)=(-p-6)(9p-6)=(p+6)(6-9p)
г) (7m-3(2m-5))(7m+3(2m-5))=(7m-6m+15)(7m+6m-15)=(m+15)(13m-15)