问题 解答题
先观察,再根据规律,把算式填完整.
(1)22-12=3,32-22=5,72-62=13,222-______=______,______-782=______.
(2)
1
2
-
1
3
=
3-2
2×3
=
1
6
1
4
-
1
7
=______=______.
答案

(1)22-12=3,32-22=5,72-62=13,222-212=43,792-782=157.

(2)

1
2
-
1
3
=3-
2
3
×2=
1
6
1
4
-
1
7
=
7-4
4×7
=
3
28

故答案为:212,43,792,157,

7-4
4×7
3
28

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