模式是“当n取1时,显然成立
设n=k,假设1*2^1/2*3+2*2^2/3*4+3*2^3/4*5+...+k*2^k/(k+1)(k+2)=(2^k+1/k+2)-1
则n=k+1时,``````````````````````````
即是当n=k+1时结论成立”
然而,大哥,n=1时它显然不成立.题抄错了吧
模式是“当n取1时,显然成立
设n=k,假设1*2^1/2*3+2*2^2/3*4+3*2^3/4*5+...+k*2^k/(k+1)(k+2)=(2^k+1/k+2)-1
则n=k+1时,``````````````````````````
即是当n=k+1时结论成立”
然而,大哥,n=1时它显然不成立.题抄错了吧