计算:1+1/1+2+1/1+2+3+1/1+2+3+4+…+1/1+2+3+4+5+6+7+8+9+10(过程)
问题描述:
计算:1+1/1+2+1/1+2+3+1/1+2+3+4+…+1/1+2+3+4+5+6+7+8+9+10(过程)
答
1+1/1+2+1/1+2+3+1/1+2+3+4+…+1/1+2+3+4+5+6+7+8+9+10
=2/1*2+2/2*3+2/3*4+...+2/10*11
=2(1/1-1/2+1/2-1/3+...+1/19-1/11)
=2x(1-1/11)
=20/11