论文部分内容阅读
等式(a+b)2=a2+2ab+b2和(a-b)2=a2-2ab+b2统称完全平方公式,这两个公式的正向应用是同学们熟知的,此外,我们还要注意它们另外的三个“面孔”:
The equation (a+b)2=a2+2ab+b2 and (ab)2=a2-2ab+b2 are collectively referred to as the full squares formula. The positive applications of these two formulae are known to the students. In addition, we must also pay attention to Their other three “faces”: