计算.⑴﹙5x²-7x+4﹚﹙7x-6﹚.⑵﹙2x-1﹚﹙4x²+2x+1﹚.⑶﹙a+b-c﹚﹙a-b-c﹚.⑷﹙2x-3y-z﹚﹙2x-3y+z﹚.⑸﹙x-3﹚﹙x+3﹚﹙x²+9﹚.⑹﹙x-y﹚³+﹙x+y﹚³.
来源:学生作业帮助网 编辑:作业帮 时间:2024/07/20 01:05:42
![计算.⑴﹙5x²-7x+4﹚﹙7x-6﹚.⑵﹙2x-1﹚﹙4x²+2x+1﹚.⑶﹙a+b-c﹚﹙a-b-c﹚.⑷﹙2x-3y-z﹚﹙2x-3y+z﹚.⑸﹙x-3﹚﹙x+3﹚﹙x²+9﹚.⑹﹙x-y﹚³+﹙x+y﹚³.](/uploads/image/z/584644-4-4.jpg?t=%E8%AE%A1%E7%AE%97.%E2%91%B4%EF%B9%995x%26%23178%3B%EF%BC%8D7x%EF%BC%8B4%EF%B9%9A%EF%B9%997x%EF%BC%8D6%EF%B9%9A.%E2%91%B5%EF%B9%992x%EF%BC%8D1%EF%B9%9A%EF%B9%994x%26%23178%3B%EF%BC%8B2x%EF%BC%8B1%EF%B9%9A.%E2%91%B6%EF%B9%99a%EF%BC%8Bb%EF%BC%8Dc%EF%B9%9A%EF%B9%99a%EF%BC%8Db%EF%BC%8Dc%EF%B9%9A.%E2%91%B7%EF%B9%992x%EF%BC%8D3y%EF%BC%8Dz%EF%B9%9A%EF%B9%992x%EF%BC%8D3y%EF%BC%8Bz%EF%B9%9A.%E2%91%B8%EF%B9%99x%EF%BC%8D3%EF%B9%9A%EF%B9%99x%EF%BC%8B3%EF%B9%9A%EF%B9%99x%26%23178%3B%EF%BC%8B9%EF%B9%9A.%E2%91%B9%EF%B9%99x%EF%BC%8Dy%EF%B9%9A%26%23179%3B%EF%BC%8B%EF%B9%99x%EF%BC%8By%EF%B9%9A%26%23179%3B.)
xJ@Fe[w6YEB."^ě1
fvFo^{ٝ72yZf7=łpP,W_fP1`os3%!RIH6biy
2u!!Ūva+ ՚Кij䠻NGMݶ._EYh HH}.]CB7FQhY'?~,.*˗H\HE.yYL%:;9ILĘИ9Q_{nV(RϲW[ZR4CiȐ7,UDWLc3T'wވ˱_
ڛ8im4#溇xURx
计算.⑴﹙5x²-7x+4﹚﹙7x-6﹚.⑵﹙2x-1﹚﹙4x²+2x+1﹚.⑶﹙a+b-c﹚﹙a-b-c﹚.⑷﹙2x-3y-z﹚﹙2x-3y+z﹚.⑸﹙x-3﹚﹙x+3﹚﹙x²+9﹚.⑹﹙x-y﹚³+﹙x+y﹚³.
计算.⑴﹙5x²-7x+4﹚﹙7x-6﹚.⑵﹙2x-1﹚﹙4x²+2x+1﹚.⑶﹙a+b-c﹚﹙a-b-c﹚.⑷﹙2x-3y-z﹚﹙2x-3y+z﹚.⑸﹙x-3﹚﹙x+3﹚﹙x²+9﹚.⑹﹙x-y﹚³+﹙x+y﹚³.
计算.⑴﹙5x²-7x+4﹚﹙7x-6﹚.⑵﹙2x-1﹚﹙4x²+2x+1﹚.⑶﹙a+b-c﹚﹙a-b-c﹚.⑷﹙2x-3y-z﹚﹙2x-3y+z﹚.⑸﹙x-3﹚﹙x+3﹚﹙x²+9﹚.⑹﹙x-y﹚³+﹙x+y﹚³.
(1)原式=35x³-79x²+70x-24
(2)原式=(2x)³-(1)³=8x³-1.利用立方差公式x³-y³=(x-y)(x²+xy+y²)
(3)原式=(a-c)²-b²=a²-b²+c²-2ac.利用平方差公式x²-y²=(x-y)(x+y)
(4)原式=(2x-3y)²-z²=4x²+9y²-z²-12xy.利用平方差公式x²-y²=(x-y)(x+y)
(5)原式=(x²-9)(x²+9)=x^4-81
(6)原式=(x-y+x+y)[(x-y)²-(x-y)(x+y)+(x+y)²]
=2x[x²+3y²]
=2x³+6xy².利用立方和公式x³+y³=(x+y)(x²-xy+y²)