题干

在日常生活中我们经常用到密码,如取款、上网购物需要密码,有一种用因式分解法产生密码,方便记忆,其原理是:将一个多项式因式分解:例如x4﹣y4=(x2+y2)(x+y)(x﹣y),当x=8,y=9时,x2+y2=145,x+y=17,x﹣y=4则可以得到密码是145174,1741454…,等等,根据上述方法

当x=32,y=12时,对于多项式x2y﹣y3分解因式后可以形成哪些数字密码?

上一题 下一题 0.0难度 选择题 更新时间:2016-11-28 06:16:14

答案(点此获取答案解析)

解:原式=y(x2﹣y2)=y(x+y)(x﹣y),

当x=32,y=12时,y=12,x+y=44,x﹣y=20,

可以得到的数字密码是:124420,122044,441220,442012,201244,204412.

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