x^(2n+3)-x^(2n+2)+x^(2n+1)

x^2n-3x^n x^n*x^n+1*(-x)^2n*x+(-x)^2n+3x^2n-2*x (-x)^3x^n-1+x^2n(-x)^3 x^(n)*x^(n+1)+x^(2n)*x (4x^n-2x^n-1-3x^n+2)÷（-5x^n-1) 计算(x^(2n)+x^n+1)(x^(3n)-x^(2n)+1) x^n-1(3x^n+4x^n+1-5x^n+2) f(x)=e^x-x 求证(1/n)^n+(2/n)^n+...+(n/n)^n 已知集合P={x|x=2n,n∈N^+},集合Q={x|x=3n,n∈N*}.则P∩Q等于多少?,A,{x|x=n,n∈N*}B.{x|x=5n,n∈N*}C,{x|x=12n,n∈N*}D,{x|x=6n,n∈N*} C语言 f(x)=1+x+x^2/2!+x^3/3!+...+x^n/n!直到|x^n/n| 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^4n/x^2n)*x^n x^n-2x^n+1,因式分解 已知 x ^3n-2 ÷x^ n+1 =x^3-n×x^n+2,求n的值