计算:1/2+(1/3+2/3)+(1/4+2/4+3/4)+···+(1/40+2/40+···+39/40)
计算:1/2+(1/3+2/3)+(1/4+2/4+3/4)+···+(1/40+2/40+···+39/40)
计算(+1)+(-2)+(+3)+(-4)+······+(-100)+(+101)+(-102)
计算 1-2+3-4+5-6+····+(-1)^n+1*n
计算:(详细步骤和计算依据)谢谢 (1-1/2²)·(1-1/3²)·(1-1/4²)··
计算1+(-2)+3+(-4)+5+(-6)+····+(+2013)+(-2014)
怎样计算1×2+2×3+3×4+······+100×101
计算1-2+3-4+5-6+······-98+99=
计算:(2+4+6+8+···+100)-(1+3+5+···+99)
计算:1+(-2)+3+(-4)+···+2005+(-2006)+2007+(-2008).
C语言计算1+2+3+···+100
计算(1)(xy)^3·3x^2·(-4x^2y^3)^2
简便计算:1*2分之1+2*3分之1+3*4分之1······+38*39分之1+39*40分之1