题目内容
请你先认真阅读材料:
计算(-
)÷(
-
+
-
)
解:原式的倒数是(
-
+
-
)÷(-
)
=(
-
+
-
)×(-30)
=
×(-30)-
×(-30)+
×(-30)-
×(-30)
=-20-(-3)+(-5)-(-12)
=-20+3-5+12
=-10
故原式等于-
再根据你对所提供材料的理解,选择合适的方法计算:
.
计算(-
| 1 |
| 30 |
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
解:原式的倒数是(
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
| 1 |
| 30 |
=(
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
=
| 2 |
| 3 |
| 1 |
| 10 |
| 1 |
| 6 |
| 2 |
| 5 |
=-20-(-3)+(-5)-(-12)
=-20+3-5+12
=-10
故原式等于-
| 1 |
| 10 |
再根据你对所提供材料的理解,选择合适的方法计算:
|
原式的倒数是:
(
-
+
-
)÷(-
)
=(
-
+
-
)×(-42)
=-(
×42-
×42+
×42-
×42)
=-(7-9+28-12)
=-14,
故原式=-
.
(
| 1 |
| 6 |
| 3 |
| 14 |
| 2 |
| 3 |
| 2 |
| 7 |
| 1 |
| 42 |
=(
| 1 |
| 6 |
| 3 |
| 14 |
| 2 |
| 3 |
| 2 |
| 7 |
=-(
| 1 |
| 6 |
| 3 |
| 14 |
| 2 |
| 3 |
| 2 |
| 7 |
=-(7-9+28-12)
=-14,
故原式=-
| 1 |
| 14 |
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