∫[(x+2)/(x^2+2x+3)]dx ∫(dx)/(1+e^x) 感激不尽!x^2+2x+3怎么等于(x+1)(x+2)啊？……

#define F(x) x - 2 #define D(x) x*F(x) printf(%d,%d,D(3),D(D(3))) ; 等差数列中“对称设项法”,四个数x-3d x-d x+d x+3d 为什么三个数x-d x x+d 五个数x-2d x-d x x+d x+2d 四个数x-3d x-d x+d x+3d 为什么偶数个是这样的?推理过程写一下或弄个例题证明. *-----------------------------------------------*| 6 4 X | 8 X X | X X 5 || X X X | X X X | X 7 8 || X X X | X X X | X X X ||---------------+---------------+--------------- || X X X | X X X | 5 1 X || X X X | X 6 X | X X X || 8 X X | 3 5 X | 2 X X || x(x*x-6x-9)-x(x*x-8x-15)+2x(3-x) 填九宫格帮帮忙.x x 6 x x 7 x x 98 x x x 3 x 1 x x 9 x x 6 x 5 x 3 x x x 3 x x x x 1 8x x x 9 x 1 x x x2 1 x x x x 6 x x x 6 x 7 x 3 x x 1 x x 9 x 2 x x x 47 x x 8 x x 5 x x 七年级下册政治复习提纲(山东人民出版社)第五单元是 青春的脚步 青春的气息别弄错了啊!格式：X X X X X X X X X 1、X X X X X X X X X X.2、X X X X X X X X X.3、X X X X X X X X X X X. matlab中a(x)=x^4+3x^3+9x-18 b(x)=x^5-4x^3-18x+7 c(x)=x^7+6x^5+9x^3-5x^2-2 d(x)=x^9-8x^7+6x^5-4x^4+d(x)=x^9-8x^7+6x^5-4x^4+6x^2+3 求e(x)=a(x)*b(x)*c(x)*d(x) x(x-2)(x-3) {x|(x+3)(x-2) -x^3+x^2-x x×x+3x-9/ x+2 x+2x+3x+.+100x (x*x-3)*(x*x-3)-x*(x*x-3)-2x*x 因式分解 dy/d(x^2) ∫[(x^2-x+6)/(x^3+3x)]dx printf((x%2)?**%d:##%d ,x);是什么意思?#include main(){ int x; for(x=3;x Y=X^2X (X>0) 求导Y=X^2X (X>0) 求d(Y)/d(X) （x%2）?(*%d):(#%d);