(1)x^n+2 -6x^2+n +8x^2(2)x^2 -21xy +98y^2 +x -7y(3)x^2 +6xy +9y^2 -4a^2 +4ab -b^2

x^(n)*x^(n+1)+x^(2n)*x 因式分解4x^(n+2)-9x^n+6x^(n-1)-x^(n-2) 因式分解4x^n+2-9x^n+6x^n-1-x^n-2 f(x)=e^x-x 求证(1/n)^n+(2/n)^n+...+(n/n)^n 因式分解2x^n-6x^n-1-8x^n-2 若(x^2+1/x)^n(n∈N+,n 因式分解：(x^n+1)+(2x^n)+(x^n-1) x^n+1-2x^n+x^n-1因式分解 x^n-1-2x^n+x^n-1因式分解 分解因式x^n-x^(n-1)+x^(n-2) x^n-2x^n+1,因式分解 x^n*x^n+1*(-x)^2n*x+(-x)^2n+3x^2n-2*x (-x)^3x^n-1+x^2n(-x)^3 (8x^n+1-3x^n-1)-2(-x+9x^n+1-4x^n)= 约分(x^n+2)+(x^n+1)-6x^n/(2x^n+1)+5x^n-(3x^n-1) 4x^n+2-9x^n+6x^n-1-x^n-24x^(n+2)-9x^n+6x^(n-1)-x^(n-2),n是整数且大于2 (x^2n-2)(x^8n+16)(x^2n+2)(x^4n+4) 求和:1+x+x^2+.+x^n