题目内容
29×
+27×
.
| 29 |
| 28 |
| 27 |
| 28 |
29×
+27×
,
=(28+1)×
+(28-1)×
,
=28×
+1×
+28×
-1×
,
=29+
+27-
,
=(29+27)+(
-
),
=56+
,
=56
.
| 29 |
| 28 |
| 27 |
| 28 |
=(28+1)×
| 29 |
| 28 |
| 27 |
| 28 |
=28×
| 29 |
| 28 |
| 29 |
| 28 |
| 27 |
| 28 |
| 27 |
| 28 |
=29+
| 29 |
| 28 |
| 27 |
| 28 |
=(29+27)+(
| 29 |
| 28 |
| 27 |
| 28 |
=56+
| 1 |
| 14 |
=56
| 1 |
| 14 |
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