1.分解因式；X的平方减3XY减10Y的平方加X加9Y减2 2.分解因式；X的5次方加X加1

Question

如题所述

Answer 1

添项、拆项,得
x^2-3xy-10y^2+x+9y-2
=(x+2y)(x-5y)+2x+4y-x+5y-2
=(x+2y)(x-5y)+2(x+2y)-(x-5y+2)
=(x+2y)(x-5y+2)-(x-5y+2)
=(x+2y-1)(x-5y+2)
x^5+x+1
=x^5-x^2+x^2+x+1
=x^2(x^3-1)+(x^2+x+1)
=x^2(x-1)(x^2+x+1)+(x^2+x+1)
=(x^3-x^2)(x^2+x+1)+(x^2+x+1)
=(x^3-x^2+1)(x^2+x+1)