用平方差公式进行因式分解 计算①4(x+y)²-9(x-y)²②9m²(a-b)³-49(b-a)³③(x+y-z)²-(x-y+z)²④x-x²-y+y²⑤(3x-y)²-4x²⑥(x+y)²-x²y²★⑦

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用平方差公式进行因式分解 计算①4(x+y)²-9(x-y)²②9m²(a-b)³-49(b-a)³③(x+y-z)²-(x-y+z)²④x-x²-y+y²⑤(3x-y)²-4x²⑥(x+y)²-x²y²★⑦
用平方差公式进行因式分解 计算
①4(x+y)²-9(x-y)²
②9m²(a-b)³-49(b-a)³
③(x+y-z)²-(x-y+z)²
④x-x²-y+y²
⑤(3x-y)²-4x²
⑥(x+y)²-x²y²
★⑦(2+1)(2²+1)(2的四次方+1)···(2的三十二次方+1)

用平方差公式进行因式分解 计算①4(x+y)²-9(x-y)²②9m²(a-b)³-49(b-a)³③(x+y-z)²-(x-y+z)²④x-x²-y+y²⑤(3x-y)²-4x²⑥(x+y)²-x²y²★⑦
1、4(x+y)2-9(x-y)2=[2(x+y)+3(x-y)][2(x+y)-3(x-y)]=(5x-y)(-x+5y)=-5x2-5y2+26xy
2、=[3m(a-b)+7*(b-a)]*[3m(a-b)-7(b-a)]=……
3、=[(x+y-z)+(x-y+z)]*[(x+y-z)-(x-y+z)]=
4、=(x-y)-(x平方-y平方)=(x-y)-(x-y)*(x+y)=(x-y)*(1-x-y)
5、6题和前面算法一样,不再叙述
第七题只要在前面乘上一个(2-1)就可以累乘进去,不难的,自己算算吧

① 4(x+y)²-9(x-y)²
原式=【2(x+y)+3(x-y)】【2(x+y)-3(x-y)】
=(5x-y)(-x+5y)
=-5x²-5y²+26xy

1,=(2x+2y+3x-3y)(2x+