计算：(-x³+2x²-5)(2x²-3x+1)

(-x³+2x²-5)(2x²-3x+1)
=-x³(2x²-3x+1)+2x²(2x²-3x+1)-5(2x²-3x+1)
=-2x的5次方+3x的4次方-x³+4x的4次方-6x³+2x²-10x²+12x-5
=-2x的4次方+7x的4次方-7x³-8x²+12x-5