计算(x+2)^2+2(x+2)(x-2)-3(x-3)(x-1)还有:(x+2)(y+3)-(x+1)(y-2)

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计算(x+2)^2+2(x+2)(x-2)-3(x-3)(x-1)
还有:(x+2)(y+3)-(x+1)(y-2)


原式=x²+4x+4+2x²-8-3(x²-4x+3)

=3x²+4x-4-3x²+12x-9
=16x-13
2.原式=xy+3x+2y+6-(xy-2x+y-2)
=5x+y+8