[k(k+1)/12](3k^2+11k+10)+(k+1)(k+2) 怎么化简

问题描述:

[k(k+1)/12](3k^2+11k+10)+(k+1)(k+2) 怎么化简
结果是[(k+1)(k+2)/12][3(k+1)^2+11(k+1)+10] 不过我不知到详细的步骤

3k^2+11k+10=(3k+5)(k+2)[k(k+1)/12](3k^2+11k+10)+(k+1)(k+2)=[k(k+1)/12](3k+5)(k+2)+(k+1)(k+2)=(k+1)(k+2)[k(3k+5)/12+1]=(k+1)(k+2)[k(3k+5)+12]/12=(k+1)(k+2)(3k^2+5k+1)/12