[解析]
解:(1)x3+9x﹣10
=x3﹣x+10x﹣10
=x(x2﹣1)+10(x﹣1)
=x(x+1)(x﹣1)+10(x﹣1)
=(x﹣1)(x2+x+10);
(2)x3﹣2x2﹣5x+6
=x3﹣2x2+x﹣6x+6
=x(x2﹣2x+1)﹣6(x﹣1)
=x(x﹣1)2﹣6(x﹣1)
=(x﹣1)(x2﹣x﹣6)
=(x﹣1)(x﹣3)(x+2);
(3)x4+5x3+x2﹣20x﹣20
=x4+2x3+3x3+6x2﹣5x2﹣10x﹣10x﹣20
=x3(x+2)+3x2(x+2)﹣5x(x+2)﹣10(x+2)
=(x+2)(x3+3x2﹣5x﹣10)
=(x﹣2)(x+2)(x2+5x+5).