初二数学题(要详细过程)快!

问题描述:

初二数学题(要详细过程)快!
(1)3s分之s-2t×s+2t分之6s²=

(s-2t)/3s ×6s²/(s+2t)
=2s(s-2t)/(s+2t)
=(2s²-4st)/(s+2t)