方程为:
1/(1*2) + 1/(2*3) + 1/(3*4) + ...+ 1/x(x+1) = 2013
即:
1-1/2 + 1/2-1/3 + 1/3-1/4 + 1/x - 1/(x+1) = 2013
1-1/(x+1) = 2013
1/(x+1)=-2012
x+1=-1/2012
x=-2013/2012
即x等于负的2012分之2013
方程为:
1/(1*2) + 1/(2*3) + 1/(3*4) + ...+ 1/x(x+1) = 2013
即:
1-1/2 + 1/2-1/3 + 1/3-1/4 + 1/x - 1/(x+1) = 2013
1-1/(x+1) = 2013
1/(x+1)=-2012
x+1=-1/2012
x=-2013/2012
即x等于负的2012分之2013