杨建忠任兰州新区书记:(x^2)n+xn-1/9y^2+1/4

(x^2)n+xn-1/9y^2+1/4 若y=xn^2-3x+2_2x+1是二次函数，则n=_. 因式分解(1+x+x2+x3....+xn)2-xn 2x(x-y){2n次方}-x(y-2x){2n-1次方} 化简 A＝[1/2(y-x）^2n-(x-y)^2n-1][-2/3(x-y)^3] x*(1+y+y^2+y^3……y^n) 化简:1!x1+2!x2+3!x3+....+n!xn 1/4(x+y)+1/2(x+y)*(x+y)>=x*根号y+y*根号x 2/（x-y)+x/y-1/x 将xn-yn分解因式的结果为(x2+y2)(x+y)(x-y)，则n的值为?