问题
解答题
观察下列各式及其验证过程:2
验证:2
(1)按照上面结论猜想4
(2)根据对上述各式规律,写出用n(n为正整数,且n≥2)表示的等式并给出证明. |
答案
(1)4
=4 15
.4+ 4 15
44 15
=
,43 15
=
,43-4+4 15
=
,4(42-1)+4 15
=
,4(42-1)+4 42
=
=4+ 4 42-1
;4+ 4 15
(2)n
,n n2-1
=
•n+ n n2-1
,n+ n n2-1
=
,n2-n+n n2-1
=
,n3 n2-1
=n
.n n2-1