23y2的精選

問題詳情： 3(2x2－y2)－2(3y2－2x2)【回答】解：原式＝6x2－3y2－6y2＋4x2＝10x2－9y2.知識點：整式的加減題型：計算題...

問題詳情：先化簡，再求值：－2x2－2[3y2－2(x2－y2)＋6]，其中x＝－1，y＝－2．【回答】－2x2－2[3y2－2(x2－y2)＋6]=－2x2－2[3y2－2x2 +2y2＋6]·······················································...