(1)(x-3)(x-3)-6(x²+x-1)
=x²-6x+9-6x²-6x+6
=-5x²-12x+15
(2)(2x+1)²-(x+3)²-(x-1)²+1
=4x²+4x+1-x²-6x-9-x²+2x-1+1
=2x²-8