⑤a²-1/4b² ⑥(x-y)²/4 — (x+y)²/4 ⑦1/3x³-3x
问题描述:
⑤a²-1/4b² ⑥(x-y)²/4 — (x+y)²/4 ⑦1/3x³-3x
答
⑤a²-1/4b² =1/4(4a²-b²)=1/4(2a+b)(2a-b)⑥(x-y)²/4 — (x+y)²/4=1/4[(x-y)²-(x+y)²]=1/4(x²-2xy+y²-x²-2xy-y²)=-xy⑦1/3x³-3x =1/3x (x²-...①9(2x+y)²-4(2x-y)②(x²+x+2)²-4不好意思,请不要追问新题,采纳后,再求助,好吗?谢谢