2/1x3 + 2/3x5 + 2/5x7 +······+ 2/97x99 + 2/99x101 简便计算

2/1x3 + 2/3x5 + 2/5x7 +······+ 2/97x99 + 2/99x101 简便计算 1x2+2x3+3x4+4x5······100x101答案是几? 1x1-2x2+3x3-4x4+5x5-6x6.-100x100+101x101 C语言编程s(x)=x-x3/3!+x5/5!-x7/7!+……+(-1)n-1·x2n-1/(2n-1)! 1/1x3+1/3x5+1/5x7+……+1/99x101 经典奥数题11/1x3+1/3x5+1/5x7.1/99x101解题思路请写清楚 2/1x3+2/3X5+2/5x7=2/7x9+2/9x11 2/1X3+2/3X5+2/5x7+.+2/19x21 已知1-1/3=2/1x3,计算1/1x3+1/3x5+1/5x7+1/7x9+1/9x11= 2/1x2+2/2x3+2/3x4+2/4x5+...+2/98x99+2/99x100 1/1x2+1/2x3+1/3x4+1/4x5+.+1/98x99+1/99x100 1/1X2+1/2x3+1/3x4+1/4x5+.+1/98x99+1/99x100求结果!