等差数列公式大全
a<Object: word/embeddings/oleObject1.bin>
=<Object: word/embeddings/oleObject2.bin>
（注意：（1）此公式对于一切数列均成立
（2）<Object: word/embeddings/oleObject3.bin>
不是对一切正整数n都成立，而是局限于n
≥2）等差数列通项公式：
<Object: word/embeddings/oleObject4.bin>
=<Object: word/embeddings/oleObject5.bin>
+（n-1）d
<Object: word/embeddings/oleObject6.bin>
=<Object: word/embeddings/oleObject7.bin>
+(n-m)d
<Object: word/embeddings/oleObject8.bin>
d=<Object: word/embeddings/oleObject9.bin>
(重要)
若{<Object: word/embeddings/oleObject10. ...